The discussion regarding the proper conclusion of the blessing for Torah study, known as Birkat HaTorah, is found in the Gemara in the tractate of Brachos on Daf Yud Alef Amud Beis. Specifically, the commentary of Tosfos, in the section addressing the correct version of the text, establishes that the blessing should conclude with the phrase Baruch Ata Hashem Hamelamed Torah LeAmo Yisrael. This version identifies the blessing as an acknowledgment of the One who teaches Torah to His people, Israel.
In contrast, Tosfos explicitly rejects an alternative version that would conclude with the words Baruch Ata Hashem Lamedeni Chukecha. Although this phrase is a scriptural verse found in the book of Tehillim, specifically in Tehillim 119:12, it does not serve as a valid liturgical formula for this blessing. The reasoning provided is that the verse is not a blessing of praise, but rather a personal request for guidance uttered by Dovid HaMelech. Because the essence of the phrase is a petition for God to teach His laws rather than a formal blessing, it cannot be used as the conclusion for this specific prayer.