Rav Shabsai Sheftl Horowitz II (1590-1660). The son of the Shelah Hakodesh, Reb Shabsai studied under his father and under Rav Shlomo Ephraim Lunshitz. After his father left for Eretz Yisrael, he became dayan of Prague. He then became Rav of Fuerth, then Frankfurt am Main, then Posen, where he founded a yeshiva. In 1654, he was appointed Rav of Vienna. In 1649, he published his father’s work, Shnei Luchos HaBris, along with his own extensive introduction, Vavei HaAmudim.
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