In 1918, he became dayan of Trzebinia and rabbi in 1923. There he established a yeshivah, Kokhov MiYaakov. During the Second World War, after taking refuge in Lvov, he was deported to Siberia in 1940 and lived for a time in Bukharia. In 1946, he settled in Israel, where his wife died in 1947. He then married Reizel, the daughter of R. Moses Lieberman of Kosice. He became the head of the yeshivah Hayyei Olam and then established his own yeshivah Kokhov MiYaakov. His principal work of Jewish law is titled "Dovev Meisharim (Pt. 1, Trebin, 1937; reprinted with Pt. 2, Jerusalem, 1958).