Aaron ben Moses ben Asher

Aaron ben Moses ben Asher (Hebrew: אהרון בן משה בן אשר‎; Tiberian Hebrew: ʾAhărôn ben Mōšeh benʾĀšēr) (10th century, died c.960) was a Jewish scribe who lived in Tiberias in northern Israel and refined the Tiberian system of writing vowel sounds in Hebrew, which is still in use today, and serves as the basis for grammatical analysis.

For over a thousand years ben Asher has been regarded by Jews of all streams as having produced the most accurate version of the Masoretic Text. Since his day, both handwritten manuscripts of the Tanakh and printed versions strove to follow his system and continue to do so. He lived and worked in the city of Tiberias on the western shore of the Sea of Galilee.

Ben Asher was descended from a long line of Masoretes, starting with someone called Asher, but nothing is known about them other than their names. His father, Moses ben Asher, is credited with writing the Cairo Codex of the Prophets (895 CE). If authentic, it is among the oldest manuscripts containing a large proportion of the Hebrew Bible. Umberto Cassuto used this manuscript as the basis of his edition of the Hebrew Bible. Aaron ben Asher himself added vowelization and cantillation notes, and mesorah to the Aleppo Codex, correcting its letter-text according to the masorah.

Maimonides accepted the views of ben Asher only in regard to open and closed sections, but apparently admired his work generally and helped to establish and spread his authority. Referring to a Bible manuscript then in Egypt, Maimonides wrote: "All relied on it, since it was corrected by ben Asher and was worked on and analyzed by him for many years, and was proofread many times in accordance with the masorah, and I based myself on this manuscript in the Sefer Torah that I wrote".

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