Opinions differ on whether he was the same person as Onkelos, who composed the leading Aramaic translation of the Pentateuch, known as Targum Onkelus. The names "Onkelos the proselyte" and "Aquilas the proselyte" are frequently interchanged in the Babylonian Talmud and Jerusalem Talmud. It is not clear how much of the Aramaic translation was based on the Greek.
Greek translation
Only fragments of this translation have survived in what remains of fragmentary documents taken from the Books of Kings and the Psalms found in the old Cairo Geniza in Fustat, Egypt, while excerpts taken from the Hexapla written in the glosses of certain manuscripts of the Septuagint were collected earlier and published by Frederick Field in his momentous work, Origenis Hexaplorum quæ Supersunt, Oxford, 1875. Epiphanius' De Ponderibus et Mensuris preserves a tradition that he was a kinsman of the Roman emperor Hadrian, who employed him in rebuilding Jerusalem as Aelia Capitolina, and that Aquila was converted to Christianity but, on being reproved for practicing astrology, 'apostatized' to Judaism. He is said also to have been a disciple of Rabbi Akiva. In Jewish writings he is referred to as עקילס and אונקלוס. Aquila's version is said to have been used in place of the Septuagint in Greek-speaking synagogues. The Christians generally disliked it, alleging that it rendered the Messianic passages incorrectly, but Jerome and Origenspeak in its praise. Origen incorporated it in his Hexapla. The Hexapla were the only known extant fragments of the work until 1897, when fragments of two codices were brought to the Cambridge University Library. These have been published: the fragments containing 1 Kings 20:7-17; 2 Kings 23:12-27 by Francis Crawford Burkitt in 1897, those containing parts of Psalms 90-103 by C. Taylor in 1899. A fuller discussion appears in the Jewish Encyclopedia. The surviving fragments of this translation, and of other Greek translations forming part of Origen's Hexapla, are now being re-published by an international group of Septuagint scholars. This work is being carried out as The Hexapla Project under the auspices of the International Organization for Septuagint and Cognate Studies, and directed by Peter J. Gentry, Alison G. Salvesen, and Bas ter Haar Romeny.
Early Rabbinic reference to Aquila's conversion
The following story about Aquila’s conversion appears in Midrash Rabbah:
