AḤAI BEN JOSIAH (end of second century), Babylonian halakhist at the close of the tannaitic period. His father Josiah was a pupil of R. Ishmael. Aḥai's statements are quoted several times in the halakhic Midrashim of the school of Ishmael, the Mekhilta on Exodus and the Sifre on Numbers. Toward the end of Judah ha-Nasi's life Aḥai placed the inhabitants of a certain town in Babylonia under the ban because they had desecrated the Sabbath (Kid. 72a). Among Aḥai's adages are "He who gazes at a woman is bound to come to sin, and he who looks even at a woman's heel will have unworthy children" (Ned. 20a); "He who buys grain in the market is like an infant whose mother has died and who is taken from one wet nurse to another, but is never satisfied… But he who eats of his own produce is like an infant raised at his mother's breast" (ARN1, 31). He applied the verse "Thou shalt not deliver unto his master a bondman" (Deut. 23:16) to a slave who escaped from another land to Ereẓ Israel (Git. 45a). It is assumed that he established the yeshivah in Ḥuzal in Babylonia, known after his death as "the school of Aḥai," which was famous in the early third century and became the nucleus of Rav's yeshivah (TJ, Av. Zar. 4:1, 43d; Ma'as. 4:6, 51c)
Hyman, Toledot, 136; Bacher, Tann; Epstein, Tanna'im, 571–2; Halevy, Dorot, 2 (1923), 182–4.