 Schonfeld was the son of Avigdor (Victor) Schonfeld, rabbi of the Adath Yisroel Synagogue and founder and principal of what became known as the Avigdor School (posthumously named in his honour).In 1940 he married Judith Hertz, daughter of the aforementioned Chief Rabbi Joseph H. Hertz, with whom he had three sons between 1940 and 1951.Schonfeld died in 1984 of a long-term brain tumour.