Isaac ben Judah HaLevi (Hebrew: יצחק בן יהודה הלוי) was a French exegete and tosafist; lived at Sens, probably, in the second half of the thirteenth century.^[1][2]

He was the pupil of Haim of Falaise, whom Heinrich Gross identifies with Chaim Paltiel.^[1]

Isaac compiled, under the title "Pa'aneaḥ Raza" (Hebrew: פענח רזא), a commentary on the Pentateuch, in which literal interpretations ("peshaṭ") are frequently intermingled with "Noṭariḳon" and "Gemaṭriot." The authorities quoted by Isaac are Joseph Ḳara, Joseph Bekor Shor, Judah he-Ḥasid, Eleazar of Worms, Haim of Falaise, and many other tosafists. The "Pa'aneaḥ Raza" was first published at Prague in 1607, from an incomplete manuscript, by Isaac Cohen, the son-in-law of Jacob Mölin. Complete copies of the work, with a postscript, and a poem containing the name of the compiler in acrostic, are extant in manuscript in the Bodleian and other European libraries.^[1]

Isaac wrote Tosafot to the Talmud, and is called "Ba'al Tosafot mi-Shanẓ" (="The Tosafist of Sens").^[1]