Aaron ben-Aser, or Aaron bar-Moses
a celebrated Jewish rabbi, lived in the first half of the 14th century. He is the author of a Treatise on the Accents of the Hebrew Language, printed in 1517. Aaron collected the various readings of the Old Testament in the manuscripts of the libraries of the West, while his collaborator, Ben- Nephthali, searched for various readings in the Eastern libraries. These variations of the text, though purely grammatical, gave rise to two celebrated sects among the Jews — that of the Occidentals, who followed Ben-Aser; — and that of the Orientals, which only admitted the authority of Ben-Nephthali. Their editions give for the first time the vowel signs, the invention of which has therefore frequently been ascribed to them. The works of Aaron ben-Aser have been printed, together with those of Moses ben-David, at the end of the Biblia Rabbinica of Venice — Hoefer, Biographie Generale, 1, 7.