[1] He waged a strong campaign, continued by his disciple Pirqoi ben Baboi, for the acceptance of the Babylonian Talmud as the standard for Jewish law in all countries.
Yehudai argued that, as a result of Byzantine persecution, the Jews of Eretz Yisrael had only preserved Jewish tradition in a fragmentary and unreliable form.
Halachot Ketzuvot is attributed to him, in which he ruled that women should, among other things, submit silently to beatings by their husbands; no other parallel by the Babylonian gaonim has been found.
[4] However the legitimacy of this text has also been called into question; many anonymous sources from the Geonic period were attributed to Yehudai Gaon by sages from the Middle Ages because of his great standing and influence.
One rabbinic school of thought credits him with authorship of the Halachot Gedolot, or of the core of it, though it is generally agreed that the final form of that work is to be attributed to Simeon Kayyara.