German rabbi; born at Prague at the end of the sixteenth century; died at Posen about the middle of the seventeenth century. He was the son of Isaac ben Samson ha-Kohen, and, on his mother's side, a grandson of the renowned L�w ben Bezaleel, rabbi of Prague. His brother Naphtali was rabbi at Lublin, and his sister was Eva BACHARACH (2). From 1628 to 1630 he was rabbi at Frankfort-on-the-Main. The earliest proof of his activity there is a regulation regarding the election of representatives of the congregation. In another document he limits the lectures of learned members of the congregation to the hours from 2 to 4 o'clock on Sabbath afternoon, while he reserves the morning hours of the Sabbath to himself. Among his hearers was Joseph Hahn, who speaks highly of him in his "Yosif Ome?" (�� 520, 529, 729). In 1630 he accepted a call to Posen, where also he was held in high esteem (preface to "?awwot Yair"). In David Oppenheimer's collection is a manuscript written by ?ayyim's nephew and disciple,Samson Bacharach, which contains ?ayyim's novell� and explanations to the four codes of the Shul?an 'Aruk.