Gra on trup, in Ki Tisa

Summary: Part of a series of posts focusing on the Vilna Gaon's interpretations of trup, this focuses on his interpretation of the munach revii on he'ashir lo` yarbeh, from Shemot 30:15's discussion of machtzis hashekel. 

Post: Beside the "famous" derasha on Vayigash Elav Yehuda, the Gra makes other derashot upon the trup on certain verses, relating them to maamarei Chazal. This is one one such derasha. In Kol Eliyahu, on page 31, he writes:

In the verse "he'ashir lo yarbeh vehadal lo yam'it, etc.," behold the melodies of the words he'ashir lo yarbeh are munach revii. And there is to explain that it comes to hint upon their statement, za"l, in masechet Ketubot (50a): "If a man desires to spend liberally {in charity} he should not spend liberally more than a fifth." And this is munach revii, the intent being that even the wealthy man should not increase more than a fifth {of his wealth}, but rather four portions he should leave for himself, and the fifth portion he should spend liberally {on charity}.


The same "objection" of the meaning of revia I discussed in the Vayigash post applies; as well as the mechanical nature of trup. In addition, the gemara there in Ketubot gives a prooftext of Bereishit 28:22, in Yaakov's vow:

כב  וְהָאֶבֶן הַזֹּאת, אֲשֶׁר-שַׂמְתִּי מַצֵּבָה--יִהְיֶה, בֵּית אֱלֹהִים; וְכֹל אֲשֶׁר תִּתֶּן-לִי, עַשֵּׂר אֲעַשְּׂרֶנּוּ לָךְ.

22 and this stone, which I have set up for a pillar, shall be God's house; and of all that Thou shalt give me I will surely give the tenth unto Thee.'

with the duplication of  עַשֵּׂר אֲעַשְּׂרֶנּוּ meaning 1/10 + 1/10 = 2/10 = 1/5. Also, repetition of this methodology might make it clear that the Gra intends this seriously, and not as a mere cute derash. Indeed, I think his comments on parshat Shemini almost demand such an interpretation. (But more about that later.)