Judah Ben Samuel of Regensburg

Judah ben Samuel of Regensburg (born 1140 in Speyer - Feb. 22, 1217 in Regensburg), also called HeHasid or 'the Pious' in Hebrew, was the initiator of the Chassidei Ashkenaz, a movement of Jewish mysticism in Germany considered different from kabbalistic mysticism because it emphasizes specific prayer and moral conduct.

Judah settled in Regensburg in 1195. He wrote Sefer Hasidim (Book of the Pious), Sefer Gematriyot (a book on astrology) and Sefer Hakavod (Book of Glory), the latter has been lost and is only known by quotations that other authors have made from it. His most prominent students were Elazar Rokeach and Moses ben Jacob of Coucy.

Rabbi Avraham Aharon Price, a 20th century rabbi, wrote a commentary on Sefer Hasidim of the same title.