Is it היו or יהיו פני הכרובים?

Summary: The Rashba answers a query, based on the texts before him and bolstered by sevarah.

Post: Similar phrases occur in parashat Terumah and parashat Vayakhel:

שמות פרק כה

• פסוק כ: וְהָיוּ הַכְּרֻבִים פֹּרְשֵׂי כְנָפַיִם לְמַעְלָה, סֹכְכִים בְּכַנְפֵיהֶם עַל-הַכַּפֹּרֶת, וּפְנֵיהֶם, אִישׁ אֶל-אָחִיו; אֶל-הַכַּפֹּרֶת--יִהְיוּ, פְּנֵי הַכְּרֻבִים. 

שמות פרק לז

• פסוק ט: וַיִּהְיוּ הַכְּרֻבִים פֹּרְשֵׂי כְנָפַיִם לְמַעְלָה, סֹכְכִים בְּכַנְפֵיהֶם עַל-הַכַּפֹּרֶת, וּפְנֵיהֶם, אִישׁ אֶל-אָחִיו; אֶל-הַכַּפֹּרֶת--הָיוּ, פְּנֵי הַכְּרֻבִים. 

Minchas Shai reports an interesting shayla which came before the Rashba:

"היו פני -- The Rashba wrote: You have written to be that there are in {your} sifrei Torah both in parashat Terumah and in parashat Vayakhel the words יהיו פני הכרובים, and in a few sefarim are written in parashat Terumah יהיו and in parashat Vayahkel היו. Such is written in our sefarim -- in parashat Terumah, which is a command, is written יהיו and in parshat Vayakhel, which pertains to the actual performance, is written היו." 

This accords with our own sefarim. Besides the testimony and explanation, I would note that the Samaritan text also accords with our (and the Rashba's) text, and Vetus Testamentum does not record any Jewish variants. We might have expected Samaritan scribes to harmonize, but they don't. If anything, they harmonize out the ויהיו in the beginning of the verse to match the היו at the end. So perhaps this can be taken as further evidence, as it goes against the grain of Samaritan emendation.

The etymology of Ashtei-Esrei

I responded to this in a comment thread on this post, but it is post-worthy in and of itself, so here goes. An Anonymous commenter asked:

11 in modern Hebrew is "Echad-Esreh".

What is the etymological origin of the different word for 11 in the Torah (eg Shmos 36:14): "Ashtei-Esreh"?

My response was as follows:

I've seen an etymology of a contraction 'ad-shtei esrei, and absent other knowledge, this is attractive.

But I recently acquired Dr. Hayim ben Yosef Tawil's "An Akkadian Lexicon Companion for Biblical Hebrew", and he notes there that this is a cognate of Akkadian "ishten", meaning "one, unique, first". (He refers us to OA, OB on (CAD I/J 275a; AHw 400a), which is references on where to find it on cuneiform tablets, I think.) In Biblical Hebrew, he notes, it only occurs in combination with asar/esrei, meaning 'eleven'

In Akkadian (in CAD I/J 279b) there is the word ishteneshret, which is a cognate of the word eleven in Biblical Hebrew.

So, I suppose, it has no relation to shtayim, but due to historical linguistic accident, this word in this form got carried in to Biblical Hebrew, even though it did not in the general case.

I would note that he has no entry I can find for echad/achat, such that I guess Akkadian did not have such a word, but rather only 'ishten.

Should Shemot 35:35 read כל or בכל?

Summary: Exploring a variant raised and rejected by Minchas Shai.

Post: In parashat Vayakhel, Shemot 35:35:

35. He imbued them with wisdom of the heart, to do all sorts of work of a craftsman and a master worker and an embroiderer with blue, purple, and crimson wool, and linen and [of] weavers, those who do every [manner of] work, and master weavers.

לה. מִלֵּא אֹתָם חָכְמַת לֵב לַעֲשׂוֹת כָּל מְלֶאכֶת חָרָשׁ וְחֹשֵׁב וְרֹקֵם בַּתְּכֵלֶת וּבָאַרְגָּמָן בְּתוֹלַעַת הַשָּׁנִי וּבַשֵּׁשׁ וְאֹרֵג עֹשֵׂי כָּל מְלָאכָה וְחֹשְׁבֵי מַחֲשָׁבֹת:

Minchat Shai points us to a variant text, which he rejects:

"In the Chumash with Targum, Savyonita printing, it is written in the margin, 'there are sefarim with בכל." And the printers simply encountered erroneous sefarim, and there is no dispute in it."

Because Shadal frequently refers to it in Ohev Ger, I recently included this particular Chumash in my weekly source-roundup. Here is the relevant text:

See the words yesh sefarim bakol on the right hand margin. Should we really move on? Is there nothing to see here?

Well, I should note that the Samaritan Pentateuch has an identical reading. To cite Vetus Testamentum:

The text on the right is our Masoretic text, while the text on the left is the Samaritan. See how כל is replaced by בכל. (No, no text I know of has מכל, which would nicely round out the set.) Just because the Samaritan Torah has this does not mean that it is any better than our own Masoretic text which lacks it. As I've noted many times in the past, there is a conscious agenda by the Samaritan scribes to smooth out the text. And I would note that we have the following context:

שמות פרק לא

• פסוק ה: וּבַחֲרֹשֶׁת אֶבֶן לְמַלֹּאת, וּבַחֲרֹשֶׁת עֵץ; לַעֲשׂוֹת, בְּכָל-מְלָאכָה. 

שמות פרק לה

• פסוק ל"ג: וּבַחֲרֹשֶׁת אֶבֶן לְמַלֹּאת, וּבַחֲרֹשֶׁת עֵץ; לַעֲשׂוֹת, בְּכָל-מְלֶאכֶת מַחֲשָׁבֶת. 

Having כל instead of בכל stands out as an exception, and so we would expect Samaritan scribes to deliberately harmonize it. We would also expect scribes, even scribes without an agenda, to unconsciously hear and then write the common phrase instead of the uncommon phrase.

Vetus Testamentum gives us one instance of a Samaritan text which lacks the ב. And it gives us a list of Hebrew texts which do have the ב. Thus:

This is quite a number of texts. Still, they may all copy off of one erroneous original, which does not have to be the Samaritan text since, as I explained above, it is an easy accidental error to make. I would side in this with Minchas Shai that כל is correct. But there might be more of a "dispute" than he anticipated.

(I see nothing in Peshitta or the LXX to indicate agreement with this.)

The pesik in Et | Mizbach HaOlah

Summary: Should we indeed darshen the trup in this way?

Post: In the recently published Birkat Avraham, by R' Avraham Albert, on Vayakhel:

He is trying to darshen the following pesik, which I underlined in red:

to refer to this special covering mentioned by Rashi (and earlier, Rabbi Yehuda in Yerushalmi Yoma 4:6 and in Bemidbar Rabba), which they used to cover the fire as they traveled with the Mishkan so that it would not go out.

I like considering cases when people darshen the trup to mean various things. Why one would darshen the pesik specifically to indicate something extra, as opposed to an attempt to separate one concept from another, I don't know. Perhaps he has a consistent theory about this which I'll understand after reading more of his sefer. (Indeed, he does seem to. See here about the function of azla geresh.) I would say that we could just darshen as Chazal often darshen, that et is leRabbot, to include something else. I suppose we could say that be introducing the slight pause of pesik, it highlights the et even more, giving us reason to treat it as more that the simple grammatically required object-marker.

However, I would take issue with this. First, this is not a pesik. It certainly shares the same sign, but it is not a pesik, which is the lightest of all possible divisions. Rather, the symbol combines with the munach under the word et to mark et with a munach legarmeih, which is a disjunctive, pausal accent, rather than a simple munach which is a mesharet. The reason the munach legarmeih appears is the reason given by William Wickes -- there is a continuous dichotomy, dividing and dividing again phrases into two parts, and it operates so long as there are at least three words in a phrase. And et mizback ha'olah is a phrase of three words, and the trup which subdivides a phrase ending in revia (which appears on the word haOlah) is the munach legarmeih.

Rav Amnon Bazak at Etz Chaim of Kew Gardens Hills

From the Etz Chaim shul bulletin:

SCHOLAR IN RESIDENCE: RAV AMNON BAZAK, Yeshivat Har Etzion
Shabbat Vayakhel, February 25^th 
This week we will host Rav Amnon Bazak of Yeshivat Har Etzion, sponsored by Marc Singer:
                Oneg and Shiur: Friday night 8:30 at the Rabinovich home, followed by a tish 
                Rav Bazak will deliver the Drasha Shabbat morning
                Shiur one hour before.Mincha {Josh: meaning the shiur is at 4:15, on "The Secret of the Copper Vessels"}

                Shiur between Mincha and Maariv {on Mordechai, Esther and the Issue of Jewish Identity in the Diaspora}
                Motzaei Shabbat at 8:30: Panel on the Legacy of Rav Yehuda Amital, zt'lThe Scholar in Residence is jointly sponsored by Ezra and Adina Dyckman and family and Dr. Marc Singer in memory of our dear friend, Danny Berkowitz, whose shiva is concluding today: Dovid Avrohom Nitanel Ben Harav Yaacov Yosef Zvi. May our learning be a z’chus for him. Don’t miss this fascinating opportunity.

Some thoughts on Onkelos on Vayakhel

Summary: Regarding three points -- the word shaba as a back-formation; Onkelos' rendition of al hanashim as al neshaya; and whether ve'asah should be rendered in Onkelos as a part tense verb.


Post: Two short points here sparked by Onkelos. The first is that I thought I would note the interesting word in Onkelos towards the very beginning of parashat Vayakhel:

לה,ב שֵׁשֶׁת יָמִים, תֵּעָשֶׂה מְלָאכָה, וּבַיּוֹם הַשְּׁבִיעִי יִהְיֶה לָכֶם קֹדֶשׁ שַׁבַּת שַׁבָּתוֹן, לַה; כָּל-הָעֹשֶׂה בוֹ מְלָאכָה, יוּמָת.	שִׁתָּא יוֹמִין, תִּתְעֲבֵיד עֲבִידְתָא, וּבְיוֹמָא שְׁבִיעָאָה יְהֵי לְכוֹן קֻדְשָׁא שַׁבָּא שַׁבְּתָא, קֳדָם יְיָ; כָּל דְּיַעֲבֵיד בֵּיהּ עֲבִידְתָא, יִתְקְטִיל.
לה,ג לֹא-תְבַעֲרוּ אֵשׁ, בְּכֹל מֹשְׁבֹתֵיכֶם, בְּיוֹם, הַשַּׁבָּת.  {פ}	לָא תְּבַעֲרוּן אִישָׁתָא, בְּכֹל מוֹתְבָנֵיכוֹן, בְּיוֹמָא, דְּשַׁבְּתָא.  {פ}

Assuming I recall correctly, I recall from several years back how Dr. Steiner gave this as an example of a back-formation. That is, language develops organically, and sometimes people reanalyze words in ways other than their initial etymology, which is then demonstrated by other forms. In this case, Shabbat is somehow Shabba in Aramaic. Why? Because שַׁבַּת looks like the construct form, "the day of rest of", it was taken as such. And then, to make the absolute form, we end up with Shabba.

Shadal in Ohev Ger notes a variant text of Onkelos, קע"א which does not have this back-formation. At least if I understand Shadal correctly.

In terms of the somewhat strange vowel pattern for Shevata, which does not accord with machon mamre (above) or with my Mikraos Gedolos, see also that dfus Savyonita has it as well:

Without getting into grammatical analyses, I suppose that it does make sense that the Aramaic translation of Shabbaton should differ from that of Ha-Shabbat.

Another thing Shadal mentions is the regarding the men coming with the women:

לה,כב וַיָּבֹאוּ הָאֲנָשִׁים, עַל-הַנָּשִׁים; כֹּל נְדִיב לֵב, הֵבִיאוּ חָח וָנֶזֶם וְטַבַּעַת וְכוּמָז כָּל-כְּלִי זָהָב, וְכָל-אִישׁ, אֲשֶׁר הֵנִיף תְּנוּפַת זָהָב לַיהוָה.

וּמֵיתַן גֻּבְרַיָּא, עַל נְשַׁיָּא; כֹּל דְּאִתְרְעִי לִבֵּיהּ, אֵיתִיאוּ שֵׁירִין וְשַׁבִּין וְעִזְקָן וּמָחוֹךְ כָּל מָן דִּדְהַב, וְכָל גְּבַר, דַּאֲרֵים אֲרָמוּת דַּהְבָּא קֳדָם יְיָ.

Shadal notes the textual evidence, and that a whole bunch of texts of Onkelos have עם rather than על, and that he thinks this is correct. And in קע"א it has על but on the margin, it notes that other seforim have עם:


I agree that on a peshat level, the pasuk means im. And this is how Rashi explains it, and how Ibn Ezra explains it.

In 2008, I noted a comment in Rashi which is likely not by Rashi:

with the women Heb. עַל הַנָּשִׁים, lit., [the jewelry was still] on the women. The men came with the women and [stood] near them. (The reason the Targum [Onkelos] left the passage in its simple sense is that he does not render וַיָּבֹאוּ הָאִנָשִׁים as וַאִתוֹ גַבְרַיָא, and the men came, but he renders: וּמַיְתַן, [and the men] brought, meaning that they brought bracelets and earrings while they were still on [i.e., being worn by] the women, as Rashi writes on “spun the goat hair” (verse 26), [which signifies that the women spun the hair while it was still on the goats].)

See my comments in that post, where I explain that why I do not think that Rashi wrote this comment in parenthesis, and furthermore why I don't believe that Onkelos really intended what was suggested in the comment, but is rather translating literally and thus refraining from commenting.

I think I would part ways with Shadal here as to what is more likely original. Onkelos is allowed to be absolutely literal and in this way refrain from commenting. But the result looks strange and is at odds with Rashi on the verse. It sounds reasonable for a sofer to emend the text to accord with Rashi, rather than in the other direction. (Though the argument can be made for an overly literal sofer who saw al as one letter off than im and so corrected it.)

But more than that, I could make an argument from absence. If Onkelos were indeed in accord with Rashi on this pasuk, I would have expected Rashi to cite this as evidence, with, for example, כתרגומו. That he doesn't, and that a girsa exists in which Onkelos does not bolster Rashi, is perhaps telling in which girsa lay before Rashi.

(See also the discussion on al vs. im here.)

The third and last point is regarding the first pasuk in perek 36. But we need to get a running jump:

לה,ל וַיֹּאמֶר מֹשֶׁה אֶל-בְּנֵי יִשְׂרָאֵל, רְאוּ קָרָא יְהוָה בְּשֵׁם, בְּצַלְאֵל בֶּן-אוּרִי בֶן-חוּר, לְמַטֵּה יְהוּדָה.	וַאֲמַר מֹשֶׁה לִבְנֵי יִשְׂרָאֵל, חֲזוֹ דְּרַבִּי יְיָ בְּשׁוֹם, בְּצַלְאֵל בַּר אוּרִי בַּר חוּר, לְשִׁבְטָא דִּיהוּדָה.
לה,לא וַיְמַלֵּא אֹתוֹ, רוּחַ אֱלֹהִים, בְּחָכְמָה בִּתְבוּנָה וּבְדַעַת, וּבְכָל-מְלָאכָה.	וְאַשְׁלֵים עִמֵּיהּ, רוּחַ מִן קֳדָם יְיָ, בְּחָכְמָא בְּסֻכְלְתָנוּ וּבְמַדַּע, וּבְכָל עֲבִידָא.
לה,לב וְלַחְשֹׁב, מַחֲשָׁבֹת--לַעֲשֹׂת בַּזָּהָב וּבַכֶּסֶף, וּבַנְּחֹשֶׁת.	וּלְאַלָּפָא, אֻמָּנְוָן--לְמֶעֱבַד בְּדַהְבָּא וּבְכַסְפָּא, וּבִנְחָשָׁא.
לה,לג וּבַחֲרֹשֶׁת אֶבֶן לְמַלֹּאת, וּבַחֲרֹשֶׁת עֵץ; לַעֲשׂוֹת, בְּכָל-מְלֶאכֶת מַחֲשָׁבֶת.	וּבְאֻמָּנוּת אֶבֶן טָבָא לְאַשְׁלָמָא, וּבְנַגָּרוּת אָעָא; לְמֶעֱבַד, בְּכָל עֲבִידַת אֻמָּנְוָן.
לה,לד וּלְהוֹרֹת, נָתַן בְּלִבּוֹ:  הוּא, וְאָהֳלִיאָב בֶּן-אֲחִיסָמָךְ לְמַטֵּה-דָן.	וּלְאַלָּפָא, יְהַב בְּלִבֵּיהּ:  הוּא, וְאָהֳלִיאָב בַּר אֲחִיסָמָךְ לְשִׁבְטָא דְּדָן.
לה,לה מִלֵּא אֹתָם חָכְמַת-לֵב, לַעֲשׂוֹת כָּל-מְלֶאכֶת חָרָשׁ וְחֹשֵׁב, וְרֹקֵם בַּתְּכֵלֶת וּבָאַרְגָּמָן בְּתוֹלַעַת הַשָּׁנִי וּבַשֵּׁשׁ, וְאֹרֵג; עֹשֵׂי, כָּל-מְלָאכָה, וְחֹשְׁבֵי, מַחֲשָׁבֹת.	אַשְׁלֵים עִמְּהוֹן חַכִּימוּת לִבָּא, לְמֶעֱבַד כָּל עֲבִידַת נַגָּר וְאֻמָּן, וְצַיָּר בְּתַכְלָא וּבְאַרְגְּוָנָא בִּצְבַע זְהוֹרִי וּבְבוּצָא, וּמָחֵי; עָבְדֵי, כָּל עֲבִידָא, וּמַלְּפֵי, אֻמָּנְוָן.
לו,א וְעָשָׂה בְצַלְאֵל וְאָהֳלִיאָב וְכֹל אִישׁ חֲכַם-לֵב, אֲשֶׁר נָתַן יְהוָה חָכְמָה וּתְבוּנָה בָּהֵמָּה, לָדַעַת לַעֲשֹׂת, אֶת-כָּל-מְלֶאכֶת עֲבֹדַת הַקֹּדֶשׁ--לְכֹל אֲשֶׁר-צִוָּה, יְהוָה.	וְיַעֲבֵיד בְּצַלְאֵל וְאָהֳלִיאָב וְכֹל גְּבַר חַכִּים לִבָּא, דִּיהַב יְיָ חָכְמְתָא וְסֻכְלְתָנוּתָא בְּהוֹן, לְמִדַּע לְמֶעֱבַד, יָת כָּל עֲבִידַת פֻּלְחַן קֻדְשָׁא--לְכֹל דְּפַקֵּיד, יְיָ.
לו,ב וַיִּקְרָא מֹשֶׁה, אֶל-בְּצַלְאֵל וְאֶל-אָהֳלִיאָב, וְאֶל כָּל-אִישׁ חֲכַם-לֵב, אֲשֶׁר נָתַן יְהוָה חָכְמָה בְּלִבּוֹ--כֹּל אֲשֶׁר נְשָׂאוֹ לִבּוֹ, לְקָרְבָה אֶל-הַמְּלָאכָה לַעֲשֹׂת אֹתָהּ.	וּקְרָא מֹשֶׁה, לִבְצַלְאֵל וּלְאָהֳלִיאָב, וּלְכָל גְּבַר חַכִּים לִבָּא, דִּיהַב יְיָ חָכְמְתָא בְּלִבֵּיהּ--כֹּל דְּאִתְרְעִי לִבֵּיהּ, לְמִקְרַב לַעֲבִידְתָא לְמֶעֱבַד יָתַהּ.

There are two ways to parse this entire pasuk. Note that in 35:30, Moshe begins his speech. Where are the closing quotation marks? Is 36:1 part of Moshe's quote, or does the quote end at the end of 35:35, where this new verse begins to designate action?

The difference between the two is as follows. The word וְעָשָׂה would seem to designate past action. But if Moshe is telling all of Klal Yisroel how great Betzalel is, then he should be telling them that he shall do the work in the future, for he has not done the work yet. In the Targum, if we see ועבד, then it would be past tense. If we see ועביד, as one commentator on Onkelos (Chalifot Semalot) suggested emending, then it could be a present tense verb. If we see ויעביד, then it is a future tense verb.

The nusach of Onkelos above came from Mechon Mamre, though I am not certain which manuscript they chose for this.

But in our own Mikraos Gedolos, as well as in Dfus Savyonita, we have what I would expect, ועבד:

If we look to the Samaritan Targum, they translate it this way as well. If we look to the Septuagint, we get:

1 And Beseleel wrought, and Eliab and every one wise in understanding, to whom was given wisdom and knowledge, to understand to do all the works according to the holy offices, according to all things which the Lord appointed.
1 ΚΑΙ ἐποίησε Βεσελεήλ καὶ Ἐλιὰβ καὶ πᾶς σοφὸς τῇ διανοίᾳ, ᾧ ἐδόθη σοφία καὶ ἐπιστήμη ἐν αὐτοῖς συνιέναι ποιεῖν πάντα τὰ ἔργα κατὰ τὰ ἅγια καθήκοντα, κατὰ πάντα ὅσα συνέταξε Κύριος.

Thus, past tense rather than future tense. The perek changes are not Jewish in origin. They were created by Jerome, a Christian. But I would guess that the clear reason that he changes to a new perek (36) right here is that he considers Moshe's quote to have ended and this to be describing the beginning of the actual work.

The Peshitta has this as well:

though I deliberately left out the English translation, since they embed it in quotes and make it into the future tense.

Targum (Pseudo-)Yonatan has ויעבד, which to me means that he considers this part of Moshe's quote.

Shadal does not discuss this variant in Ohev Ger, and that suggests to me that all manuscripts he saw had ועבד. Yet mechon-mamre does have the future tense. Where could this come from? Perhaps this is indeed original, or perhaps it is a scholarly emendation.

To cite Chalifot Semalot,

Thus, he notes that "in all nuschaot it states ועבד. And all the chachmei leiv already commented on this nusach", etc., etc. And notes the suggestion that he had already done studying and teaching in the past, and suggests instead that he was ragil to doing this, such that a present tense verb would serve nicely, and one could readily emend Onkelos to match this.

So, he presumably did not see the nusach underlying the (Temani?) text at Mechon Mamre, which "fixes" this issue.

Yet, I don't think it is such a difficultly. If we don't want to translate like Judaica Press, who place the end quote after this pasuk and use the word "shall":

1. Bezalel and Oholiab and every wise hearted man into whom God had imbued wisdom and insight to know how to do, shall do all the work of the service of the Holy, according to all that the Lord has commanded."

א. וְעָשָׂה בְצַלְאֵל וְאָהֳלִיאָב וְכֹל אִישׁ חֲכַם לֵב אֲשֶׁר נָתַן יְ־הֹוָ־ה חָכְמָה וּתְבוּנָה בָּהֵמָּה לָדַעַת לַעֲשֹׂת אֶת כָּל מְלֶאכֶת עֲבֹדַת הַקֹּדֶשׁ לְכֹל אֲשֶׁר צִוָּה יְהוָה:

then all we need do is treat it as the summarizing start of the pesukim which follow.

Sleeping on the left or right side -- a scientific and halachic perspective

No worry about kochos hachitzonim here!

Summary: Considering Chazal, Rambam, and modern science. How should one conduct oneself nowadays? This is only a beginning exploration, so one should certainly NOT rely on any of this halacha leMaaseh.

Post: According to a recent short article in the New York Times, research indicates sleeping on the left side might be deleterious for the heart and heart pressure, though it might simply be people with heart problems avoided sleeping on the left side due to discomfort. Further, that sleeping on the left side significantly increases the total amount of digestive reflux time.

What does halacha have to say about sleeping on various sides? Well, there is the gemara in Berachot 13b:

R. Joseph said: A man lying on his back should not recite the Shema'. [This implies] that he may not read [the Shema' lying on his back], but there is no objection to his sleeping in this posture. But did not R. Joshua b. Levi curse anyone who slept lying on his back?²³  In reply it was said: To sleeping thus if he turns over a little on his side there is no objection, but to read the Shema' thus is forbidden even if he turns over somewhat. But R. Johanan turned over a little and read the Scripture? — R. Johanan was an exception, because he was very corpulent.

Rashi explains there:

לייט אמאן דגני אפרקיד - שמא יתקשה אברו בתוך שנתו ונראה לרבים והוא דרך גנאי:

"Lest he develop an erection within his sleep, which would be visible to the public, and this is a disgrace."

He does NOT, as far as I can make out, consider this to be because of fear of causing a seminal emission, which would be zera levatala. (Presumably because he is lying on his back, and this leads to exposure, rather than to said hardening of the ever.)

However, see Rashi to the parallel gemara, in Niddah 14a:

אפרקיד - פניו למעלה וגנות הוא שפעמים שיתקשה אבר תוך שינתו ויתגלה ועוד שידיו מונחות לו על אברו ומתחמם:

There, the additional reason is given that his hands might cause warming of the ever.

See also Tosafot there:

לייט אמאן דגני אפרקיד. פי' בקונטרס שידיו מונחות על מילתו ומתחמם ורשב"ם פירש שבגדיו נופלין על אמתו ומתחמם ומה שפי' עוד שפעמים [מתקשה ומתגלה] לא נראה דבבית סגור או אפל מאי א"ל:

The Rif cites this give and take in the gemara, but it might just be for the sake of discussing the halachos of kriyas Shema:

Rav Yosef said: One who is lying on his back should not read Shema,
This implies that he may not read, but he may, with no problem, go to sleep such!
But Rabbi Yehoshua ben Levi cursed anyone who slept lying on his back!
In terms of sleeping, if he turns a bit to the side, it is fine, but in terms of reading {Shema}, even if he turns a bit to the side it is forbidden.

But Rabbi Yochanan would turn on his side and read {Shema}?!
Rabbi Yochanan was different, because he was fat.

Looking at Ayin Mishpat, Ner Mitzvah, I see no note for it. This would be significant, because it would mean that the Tur, Shulchan Aruch, and Rema do not bring this down lehalacha. So, while it might not be a good idea, I don't know that we should necessarily resurrect this as an issur chamur.

In Gittin 47a, we read that Resh Lakish refused a mattress offered by his daughter, because "my belly is my cushion":

אמרה ליה ברתיה לא בעית מידי למזגא עליה אמר לה בתי כריסי

And see Rashi and Tosafot there. This would appear to be during eating, not during sleeping, though.

According to this website, Mishna Berura lists sleeping on back or front as an issur gadol, in siman 239 seif katan 6, though I don't see it there. This within a discussion of saying Kriyas Shma on one's back.

The Rambam does bring down halachot of sleeping on one's side, in Hilchot Deot, perek 4, halacha 5:

ז  [ה] לֹא יִישַׁן אָדָם לֹא עַל פָּנָיו, וְלֹא עַל עָרְפּוֹ, אֵלָא עַל צִדּוֹ--בִּתְחִלַּת הַלַּיְלָה עַל צַד שְׂמֹאל, וּבְסוֹף הַלַּיְלָה עַל צַד יָמִין.  וְלֹא יִישַׁן סָמוּךְ לַאֲכִילָה, אֵלָא יַמְתִּין אַחַר אֲכִילָה כְּמוֹ שָׁלוֹשׁ אוֹ אַרְבַּע שָׁעוֹת.  וְלֹא יִישַׁן בַּיּוֹם.

However, an examination of the context reveals that this is health-advice. It was not likely based on the gemara, but of positive effects of sleeping in this manner.

Aristotle spoke of benefits of sleeping on the right side:

Q. Why do men sleep better and more at ease on the right side than on the left? A. Because when they be on the left side, the lungs do lie upon and cover the heart, which is on that side under the pap; now the heart, the fountain of life, being thus occupied and hindered with the lungs, cannot exercise its own proper operation, as being overmuch heated with the lungs lying upon it, and therefore wanting the  refreshment of the air which the lungs do give it, like the blowing of a pair of  bellows, is choked and suffocated, but by lying on the right side, those inconveniences are avoided.

Compare Rambam with the recommenation of the Arab physician Avicenna:

A short sleep after a meal is useful ; one should lie first on the right side, then on the left, and finally turn back again to the right side.

though maybe this is only after a meal. I didn't take the time, yet, to fully research this. But it certainly seems, based on cultural and textual context, that Rambam is giving medical advice. I would wonder whether something similar is actually motivating Rabbi Yehoshua ben Levi.

Turning to more recent summaries of halacha, consider the following, from Halacha Yomi:

5. A person should train himself to sleep on his side. Sleeping on one's back or on one's stomach is a severe transgression. It is beneficial to begin one's sleep while lying on the left side, and afterwards to change to the right side. 

This is beneficial to one's health, since the liver is on one's right side, and the stomach on one's left. When one leans to the left, the liver will lie on the stomach and warm it with its heat. This will hasten the digestion of the food. After the food is digested, it is preferable to lean to the right, thus allowing the stomach to rest and the wastes to descend. One should not turn frequently from side to side.

Not much in the way of explanation of what the transgression is, and where it is sourced. But once we see this medieval explanation about the liver lying on the stomach and aiding digestion, and allowing the stomach to rest, etc., I wonder strongly whether this is really binding halacha. Just as we do not listen to the cures listed in the Talmud, we should not necessarily need to listen to the health-advice. And if these recommendations are based on the Rambam, and based on medieval medicine, all the more so!

And now, it seems that according to modern medicine, it is bad for the heart and for certain types of digestion to lie on one of those sides, at least for people with digestive reflux or heart conditions.

Here is another summary. Naturally enough, kabbalah comes into it. This is unfortunate because kabbalah comes and adds mystical explanations to what is often something entirely halachic or medical. And then, with the mystical rationale in place, any efforts to overturn or reevaluate the halacha are thwarted, for there is a deep mystical reason for the practice. For example, fish with meat is a halacha motivated by a medical concern, for tzaraat. Yet kabbalists added kabbalistic reasons, which would prevent a reevaluation. Even though as metzius, or evaluation of metzius, changes, the appropriate applied halacha might change as well.

The summary is from Halachically Speaking, reviewed by Rav Yisroel Belsky:

Sleeping on one's Side

In the beginning of the night, one should sleep on his left side and at the end of the night one should sleep on his right side.(67) It is much healthier to sleep on the side because doing so allows the lungs to work better, so one gets more out of his sleep.(68)

Those footnotes:

(67)Rambam Hilchos Deos 4:5, Siddur Yaavetz page 587, Kitzur Shulchan Aruch 71:5, Kaf Ha'chaim 170:72, Tov Yehoshua page 116:10, Pela Yoetz "yemin" page 283. This applies to lefties as well (refer to Yemin Moshe pages 27 and 58). The reason is because in this way his food will be digested properly (Kitzur Shulchan Aruch 71:5). (68) Horav Yisroel Belsky Shlita.

So one is the Rambam, but then Kaf Kachaim comes into it. The explanation of lungs working better may be true -- it could also prevent snoring -- but it does not mean that such working better is what was motivating the Rambam, motivating Rabbi Yehoshua ben Levi, or that such benefit of better breathing would raise this to an obligation. The intent might have been to give modern scientific rationale, but I think one should question whether it is really a halachic obligation, especially if someone finds other sorts of sleep more comfortable.

Another discussion of this, From Halachah For Today:

1)One should not sleep on his stomach nor on his back, rather on his side.

In the beginning of the night he should sleep on his left side and at the end of the night on his right side. (Rambam Hilchos Dei’os Perek 4 Halacha 5)

One of the reasons given for this is that the liver is on the right side and the stomach is on the left side, and thus when one sleeps on the left side, the liver’s heat will warm the stomach and will help the digestive system. (Sefer Aleh L’Terufah quoted in Sefer HaLikutim back of the Shabsi Frankel edition of the Rambam. See also Kitzur Shulchan Aruch Siman 71:5)

Another reason for the prohibition of sleeping on the back or on the stomach is to prevent embarrassing situations and/or nocturnal emissions while sleeping. (See Rashi to Brachos 13b Dibur Hamaschil Layit Aman. See also Pele Yoetz, “Yemin” and Shu”t Az Nidberu Vol. 6 Siman 50 regarding if these positions apply only to when going to sleep or to any time one lays down. See also Mishna Berura Siman 239:6 where he refers to sleeping on the back or stomach as an “Issur Gadol, a big sin”) 

Lastly, there are kabalistic reasons for not sleeping on the back and the stomach. (See Kaf HaChaim Siman 238:11) 

2) This Halacha applies equally to men and women (as even though the second reason cited does not apply to women, the first and third reason do. Though for women it isn’t considered a big sin if they do not follow this Halacha) 

This Halacha also applies equally to right handed people and left handed people.

Note how the kabbalistic reason, from the Kaf KaChaim, siman 238:11, would be a reason women should keep it; together with the outdated science. What is the kabbalistic reason? That it helps a lot to nullify the kochos hachitzonim, which appear to be negative forces of tumah.

At the end of the day, the halachic reasoning would still seem to apply, though I would not be persuaded by the kabbalistic or scientific reasons. But that would be the halachic reasoning for not sleeping on one's back, rather than being particular about the left side and then the right. Even within that halachic reasoning for the back and front, I am not so convinced. This deserves further analysis. Was Rabbi Yehoshua ben Levi's reason medical, or based on embarrassment / shichvas zera levatala? While Rishonim discuss this gemara, do they bring it down lehalacha? If it is based on embarrassment, perhaps the halacha is different nowadays, since we no longer sleep in the nude.

Two further interesting discussions. One going through many of the sources in a nice organized way, and another discussing if one should wake someone up (!) who is sleeping in an improper manner.

Another Ibn Ezra on brain anatomy

Summary: which seems based on contemporary, Galenic science.

Post: We saw in a previous post, regarding zachor veShamor as referring to the same location in the brain, that Ibn Ezra relied on contemporary, Galenic science.  Consider the following pasuk, in Ki Tisa {Shemot 31:3}:

3. and I have imbued him with the spirit of God, with wisdom, with insight, with knowledge, and with [talent for] all manner of craftsmanship

ג. וָאֲמַלֵּא אֹתוֹ רוּחַ אֱ־לֹהִים בְּחָכְמָה וּבִתְבוּנָה וּבְדַעַת וּבְכָל מְלָאכָה:

What is the difference between chochma, tevunah, and daat? Well, Rashi explains it as:

with wisdom -- that which a person hears from others and learns.		בחכמה: מה שאדם שומע מאחרים ולמד:
and with insight -- understanding something from his heart, from those things which he learned.		ובתבונה: מבין דבר מלבו, מתוך דברים שלמד:
and with knowledge -- Divine inspiration.		ובדעת: רוח הקדש:

Ibn Ezra takes a different approach:

[לא, ג]
ואמלא אותו -כמו: ויהושע בן נון מלא רוח חכמה.
וכתוב: ונחה עליו רוח ה'. ופירושו: מה היא רוח ה'. והיא רוח חכמה ובינה.
החכמה - היא הצורות האצורות באחרונית מוח הראש.

ומלת תבונה –גם בינה מגזרת בין. והיא הצורה העומדת בין צורת הדעת ובין צורת החכמה, כנגד הנקב האמצעי במוח הראש. כי החכמה כנגד הנקב האחרון. והדעת המתחברת בנקבי המוח על המצח מההרגשות.
ובלשון ישמעאל קורין:
הדעת אלתכ"ייל.
והתבונה אל"פכרה.
והחכמה אל"חכמה.

והנה בצלאל היה מלא כל חכמה בחשבון ומדות וערכים ומלאכת שמים. וחכמת התולדות. וסוד הנשמה. והיה לו יתרון על כל אנשי דורו, שהיה יודע כל מלאכה כי רבים חכמי לב לא ידעו אפילו מלאכה אחת על כן כתוב: ובכל מלאכה בוי"ו.

"Chochma, Wisdom -- this is the Forms which are stored in the back of the brain in the head.
And the word tevunah, as well as binah, are from the root בין. And this is the Form {?} which stands between the form of the daat {at the front of the head} and the form of the chochma {at the back of the head} corresponding to the middle ventricle in the brain in the head. For the chochma corresponds to the rear ventricle, and the daat which is connected via the holes in the head to the forehead from the senses.


And in Arabic they call daat al-takhayul {=imagination in modern Arabic}, and tevunah they call al-pikhrah {?} and chochma they call al-hokhma."


This is further evidence that Ibn Ezra was working with a contemporary, Galenic theory of brain function. I'll quote from my previous post:

To compare to Galenic science:

Thus, there were three ventricles, or cavities, in the brain. The foremost was connected to sense impression, just as Ibn Ezra writes. The middle one conducts judgement on the sense-impressions. And the back one is memory, to allow even animals to learn from perceptions and remember associations.

This is ancient science, and was the accepted scientific orthodoxy in Ibn Ezra's time. It is not surprising for Ibn Ezra to rely on contemporary science, as he does so in many other instances.

I pointed out in the past post that our modern conception of memory does not accord with Galenic science, and thus Ibn Ezra is incorrect. A commenter, Z, comments there:

And that place is the place of the guarding of the forms

From here

Occipital Lobe - Region in the back of the brain which processes visual information. Not only is the occipital lobe mainly responsible for visual reception, it also contains association areas that help in the visual recognition of shapes and colors. Damage to this lobe can cause visual deficits

I must say that it is pretty neat. It is rather cool when medieval science, or the science of Chazal, or Ayurvedic medicine, accords with modern scientific discoveries or facts. Yet, while it may be rather neat, we should take care not to make this mean more than it does.

In any scientific system, there will be a plethora of facts, both true and false. When one overlays two scientific systems upon one another, there are bound to be overlaps. Yet those overlaps are not meaningful. Thus, one might be impressed by the kiruv proof that Chazal predicted that hemophilia is transmitted through the mother. But, as I explained in this post analyzing this claim put forth by Rabbi Feldman, the fact itself is discernible by mere observation, and one could arrive at this conclusion anyway by applying the erroneous contemporary scientific theory which Chazal propound. To cite myself further:

And we see in the gemara in Niddah (31a) that the mother contributes the blood:

Our Rabbis taught: There are three partners in man, the Holy One, blessed be He, his father and his mother. His father supplies the semen of the white substance out of which are formed the child's bones, sinews, nails, the brain in his head and the white in his eye; his mother supplies the semen of the red substance out of which is formed his skin, flesh, hair, blood and the black of his eye; and the Holy One, blessed be He, gives him the spirit and the breath, beauty of features, eyesight, the power of hearing and the ability to speak and to walk, understanding and discernment. When his time to depart from the world approaches the Holy One, blessed be He, takes away his share and leaves the shares of his father and his mother with them. R. Papa observed: It is this that people have in mind when they say, 'Shake off the salt and cast the flesh to the dog'.

Ancient Greek medicine was a well-developed system. As was Chazal's science. So is modern science. It is no wonder that, on occasion, their paths may cross. That one particular conclusion of one system is matched in a second system does not indicate that they shareassumptions. For years, people went to bloodletters, or applied leeches. This because of false beliefs about the four humours of the body. Yet, in some instances, nowadays bloodletting is a good idea, and has positive effect. This does not mean that it is because those who originally recommended leeches had a deep understanding of modern science.

Z put forth a similar comment in response to my claim that Ibn Ezra was wrong due to following Galen about the extramission theory of sight, that the eyes send forth rays and see at a distance, which is why sight is immediate, while sound takes time to travel to the person:

What do you mean that nowadays we know that its not the case? We know that the lightning happens at the same time as the thunder. We also know that sound travels thru the air in waves and each sound makes a different wave. I dont think he means that an image of the actual letter is made in the air. That would be ludicrous.

As I clarified in the comment section there, what I was speaking of was specifically the extramission theory, in which rays exit the eyes and sense at a distance, which Ibn Ezra explicitly puts forth.

Yes, it is nice when the science of the Rishonim accords with our science. But it does this because of random chance, or because the medieval science was in fact correct about some things. This is not surprising.

However, in terms of making this one part of Ibn Ezra, namely one ventricle out of three, and within that ventricle, one function out of two, correspond to the functioning of the occipital lobe, I have to first wonder what the point would be? This is just luck, that out of the many erroneous scientific points put forth, he hit upon one correct function.

I would also wonder whether the correspondence is indeed there. To cite the function of the occipital love once again:

And that place is the place of the guarding of the forms

From here

Occipital Lobe - Region in the back of the brain which processes visual information. Not only is the occipital lobe mainly responsible for visual reception, it also contains association areas that help in the visual recognition of shapes and colors. Damage to this lobe can cause visual deficits

Ibn Ezra just mentions tzuros, which might correspond to shapes, but not to colors. I suppose memory . storing of these shapes must be done in order to recognize them. Yet it might well be that Galen, and Ibn Ezra, would say that this happens in the front of the brain, where processing of perception happens. I don't know enough Galenic science to say for certain, but this is what it seems from the summary above. Further, I am not sure we know what is meant by tzurot. It certainly means something, and something important. For example (citing Wikipedia), Plato maintained that Form was distinct from substance (think chomer vs. tzurah) and that these forms have an independent, and indeed have the highest and most fundamental kind of reality. It is a sublime philosophical concept, which might well not accord precisely with what we would call forms in English, "shapes".

I'll close with Ibn Caspi's approval yet slight disagreement with Ibn Ezra, in assigning each of these three types of wisdom to the three sections of the brain:

YU Torah for parashat Vayakhel

Audio Shiurim on Vayakhel
Rabbi Yonason Sacks: Havara Lechalek Yatzas or Lelav Yatzas 
Rabbi Hershel Reichman: The Individual and the Tzibbur building the Mishkan
Rabbi Baruch Simon: Betzalel and Ahaliav - Greatness and Humility
Rabbi Hershel Schachter: Laws of Shabbos based on the Mishkan
Rabbi Daniel Z. Feldman: Chachmah  
Rabbi Ally Ehrman: The Secret Of One 
Rabbi Chaim Brovender: Bedek HaBayit 
Rabbi Michael Taubes: Kiddush and its Connection to Yitzas Mitzrayim 
Mrs. Shira Smiles: Mirroring Majesty
Rabbi Zev Reichman: The Wisdom of Betzalel 
Rabbi Aryeh Lebowitz: And Moshe gathered the people 
Mrs. Shoshana Schechter: Reflections on the Mirrors of Mitzrayim: Looking Forward to Make Change 
Rabbi Aaron Soloveichik: The Relationship between Vayakhel-Pekudei and Parah 
Rabbi Joel Finkelstein: The Hidden Angels 
Rabbi Moshe Taragin: Creativity and Shabbat 
Rabbi Etan Berman: Ain't Gonna Work on Saturday: The Roots of Meleches Shabbos
Rabbi Dovid Gottlieb: Preparing Cholent on Shabbos 

Articles on Vayakhel
Rabbi Dr. Jacob J Schacter: A Part or Apart?
Rabbi David Horwitz: Finishing the Mishkan
Rabbi Avraham Gordimer: Donors to the Mishkan 
Rabbi Shmuel Goldin: Understanding Shabbat
Rabbi Avigdor Nebenzahl: Giving Generously and Precision in Mitzvoth
Rabbi Yehuda Henkin: Priorities
Rabbi Maury Grebenau: The Jewish Space-Time Continuum
Rabbi Shlomo Einhorn: The Mindful Kli of Moshe
Rabbis Stanley M Wagner and Israel Drazin: The Tabernacle Donors and Their Contribution 

Rabbi Jeremy Wieder: Laining for Parshat Vayakhel
See all shiurim on YUTorah for Parshat Vayakhel

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