SOCHACZEW, ABRAHAM BEN ZE'EV NAHUM BORNSTEIN OF (1839–1910), Polish rabbi, head of the bet din of Sochaczew. He became famous as a child prodigy. At the age of 14 he married the daughter of Menahem Mendel of *Kotsk, in whose home he remained for ten years studying Torah and Ḥasidism. Upon his father-in-law's death, he occupied rabbinical posts in *Parczew (1862), Krosniewice (1866), *Nasielsk (1876), and *Sochaczew (1883–1910). In 1870, following the death of Ḥanokh Henyekh, leader of the *Aleksandrow Ḥasidim, he was appointed his successor, but was harassed by slanderers. Abraham founded a yeshivah and was one of the great halakhic authorities of his generation. He originated a special approach to halakhic studies and educated in his yeshivah a generation of disciples who became scholarly ḥasidic leaders. Interested in the settlement of Ereẓ Israel, he sent his son and son-in-law there in 1898 to acquire land for a religious colony, but negotiations fell through on account of the Turkish land laws. Abraham's halakhic works are Eglei Tal (1905), including a study of the laws of the Sabbath, and Avnei Nezer (1912–34), a collection of responsa on the four parts of the Shulḥan Arukh. He was succeeded as head of the Aleksandrow Ḥasidim by his only son, SAMUEL (1856–1926), who edited his father's writings and responsa on the Shulḥan Arukh, and wrote Shem mi-Shemu'el (1928–34) which sets forth many of his father's ideas on Ḥasidism.
Z.J.H. Mameluk, Abbir ha-Ro'im, 2 vols. (1935–38); Y. Raphael, Sefer ha-Ḥasidut (1955), 491–5; A.I. Bromberg, Mi-Gedolei ha-Ḥasidut, 5 (1955).