Babylonian Talmud, Kiddushin 57a

Nehemia Haimsoni was expounding on all the et’im in the Torah, explaining how each et was there to add something. As soon as he reached the verse, “You shall revere (et) the Lord your God” (Deut.10:20), he stopped. [For there is nothing to revere other than God.]His pupils asked him, “Rabbi, what will be with all the other et’im that you already expounded on?” He answered them, “Just as my attempt to interpret them all was worthy, my withdrawal from the project is equally worthy.” Until Rabbi Akiva came and expounded: “You shall revere (et) the Lord your God,” the et comes to include the students of the wise. [Translation by Rabbi Steve Greenberg]