Consider this pasuk in parashat Bo:
|יב וַיֹּאמֶר ה אֶל-מֹשֶׁה, נְטֵה יָדְךָ עַל-אֶרֶץ מִצְרַיִם בָּאַרְבֶּה, וְיַעַל, עַל-אֶרֶץ מִצְרָיִם; וְיֹאכַל אֶת-כָּל-עֵשֶׂב הָאָרֶץ, אֵת כָּל-אֲשֶׁר הִשְׁאִיר הַבָּרָד.||12 And the LORD said unto Moses: 'Stretch out thy hand over the land of Egypt for the locusts, that they may come up upon the land of Egypt, and eat every herb of the land, even all that the hail hath left.'|
How can Moshe extend his hand over the land of Egypt with locusts? Is he not extending his staff, rather than extending a locust? Indeed, in the next pasuk, Moshe explicitly extends his staff:
|יג וַיֵּט מֹשֶׁה אֶת-מַטֵּהוּ, עַל-אֶרֶץ מִצְרַיִם, וַה נִהַג רוּחַ-קָדִים בָּאָרֶץ, כָּל-הַיּוֹם הַהוּא וְכָל-הַלָּיְלָה; הַבֹּקֶר הָיָה--וְרוּחַ הַקָּדִים, נָשָׂא אֶת-הָאַרְבֶּה.||13 And Moses stretched forth his rod over the land of Egypt, and the LORD brought an east wind upon the land all that day, and all the night; and when it was morning, the east wind brought the locusts.|
Peshat is to not make a big deal about this and to explain how it means that Moshe really extended his staff. Thus, Rashi writes:
|for the locusts: For the plague of the locusts.||בארבה: בשביל מכת הארבה:|
The ב in בארבה means bishvil, for the purpose of. We could also say he is stretching his staff and thus extending locusts over Egypt.
Midrash is to read this hyper-literally and assume that Moshe was somehow commanded to extend a physical locust.
We will see both these ideas in Ibn Ezra's short and long commentary to parashat Bo. To cite Mevaser Ezra, by Rabbi Meshulam Roth,
"In his short commentary to parashat Bo, Shemot 10:12, on the word בארבה, [Ibn Ezra writes]:
בדבר הארבה, ואם כמשמעו יש לו סוד
In the matter of the locusts. And if in its [simple] implication, there is a secret there.Meanwhile, in his long commentary these are his words:
בארבה -אמר רבי משה הכהן:
כי טעם בארבה שארבה שם במטה.ואין זה נכון. רק הטעם בארבה בעבור שיבוא.
Rabbi Moshe HaKohen said that the meaning of בארבה is that there was a locust inscribed upon the staff. And this is not correct.
[Josh: as the commentary Yahel Ohr explains, the position of Rabbi Moshe HaKohen was that Moshe placed images of locusts upon the staff in order to draw with it the upper forces to bring locusts upon Egypt, and according to his words, the bringing of the locusts was via the science of the mazalot and that is why the Chacham (Ibn Ezra) said that this is not correct.]
Rather the meaning of בארבה is so that they [the locusts] will come.
And see Ohel Yosef there who brings the two versions (TODO: copy it here). --
And it appears that in his old age, in France, in his long commentary he retracted (/reviewed?) and pushed off the words of Rabbi Moshe HaKohen and cast the "secret" behind his back, so as not to reduce the miracle to bring it closer to the intellect, as was the position of Rabbi Moshe HaKohen which he had maintained at first in the short commentary in Italy.
Or, a student wrote the short commentary from his dictation and added and changed certain matters of his own accord.
And see in parashat Naso, the bitter waters, there is a secret, and this is like this matter. And so too parashat Korach, הקטרת which was known, against the plague, there is a secret, and that is like this.
[Josh: Namely, that the secret is some naturalistic explanation.]See there in the supercommentators. And all this is from the short commentary, which is associated with sefer Bamidbar.
And see earlier, I wrote in the name of the introduction to Ohel Yosef that Ibn Ezra's way was only to write Chachmeinu or Kadmoneinu, and not Rabotainu, which is not the language of Scriptures, but only the Aramaic language or Talmudic language. However, in the [Josh: long] commentary which he wrote in France, there is found in every place the language of Rabbotainu. (TODO: Record here a few examples.)"End quote.
This is interesting, to say the least.
At first, I misread the above, thinking that here he backs up the all-too-easy assertion that a talmid toeh wrote the theologically uncomfortable positions in Ibn Ezra, via a linguistic argument. Because we see all these instances of רבותינו, which Ibn Ezra wouldn't write. But this was a misreading, because he suggested that a talmid toeh recorded and added to the shorter version, while the longer version is the one with רבותינו.
So I am not sure what that linguistic argument is, exactly. Maybe that this change in word choice demonstrates that there were two separate authors.
I don't really see much difference between the shorter and the longer versions in this case. In the short version, he decides in favor of it meaning בדבר הארבה, and I would argue that this is simply because it makes for better peshat, while the inscribing locust explanation, labeled כמשמעו, is more midrashic. True, Ibn Ezra does grant it some slight purchase, but I wouldn't say that he endorses it. In the longer version, he more firmly rejects the sod, as well as explains what that sod is. Presumably he cannot reject that sod without making it clear what he is rejecting. So, while there is a change of mind, I would characterize it as a solidification of his position against the sod.
Why conceal the sod in the first place? Yahel Ohr says , ר׳׳ל זה הוא הסוד שאין ראוי לגלותו, שלא יחשבו שזה היה בכח המזל ילא במאמר השם. Perhaps. I would have guessed other answers, that (1) he doesn't want to be put in cherem by his less open-minded contemporaries, or that (2) since it involves summoning powers on high, this is Ibn Ezra's scientific / philosophical mysticism, which is nistar rather than nigleh.
See by the way Rav Saadia Gaon's Tafsir, and how he renders בארבה. I apologize for my lousy transliteration of the Judeo-Arabic:
וַיֹּאמֶר -- vekal
ה -- Allah
אֶל-מֹשֶׁה -- leMusay
נְטֵה -- mid
יָדְךָ -- yedak
עַל-אֶרֶץ מִצְרַיִם -- ilay belad Mitzr
בָּאַרְבֶּה -- bisbab al-grad ("because of the locusts")
וְיַעַל -- fi-yatz'id
עַל-אֶרֶץ מִצְרָיִם -- ilay belad Mitzr
וְיֹאכַל -- veyakul
אֶת-כָּל-עֵשֶׂב הָאָרֶץ -- gemi' 'ushbeha
אֵת כָּל-אֲשֶׁר -- gemi'
הִשְׁאִיר הַבָּרָד -- bakah al-brad