||Letter concerning family purity and ritual baths.
R. Zvi Judah b. Abraham Isaac Kook, ha-Kohen (1891–1982), rosh yeshivah. Born in Zimel, Kovno region, R. Zevi Judah was the only son of R. A.I. Kook. In 1904 he settled in Erez Israel with his parents and studied in the yeshivah Ez Hayyim in Jerusalem. He helped his father with the administration of the central yeshivah of Israel, Yeshivat Merkaz ha-Rav, and after his father's death in 1935, succeeded him as its head, together with his brother-in-law, R. Shalom Nathan-Ra'anan (d. 1972). Continuing his father's thought and method in education, he succeeded in educating thousands of pupils from all sections of the population. His positive attitude toward the State of Israel influenced the yeshivah. He published innumerable articles, mainly dealing with the halakhic attitude to topical events, and some were collected in the work Li-Netivot Yisrael (1967). He also devoted himself to editing and publishing his father's writings with source references and notes.
Following the Six-Day War the aged Rabbi Kook achieved considerable prominence as the spiritual father of Gush Emunim, and generally adopted an extreme nationalistic view, strenuously advocating the right of the Jews to the whole of Erez Israel and opposing any withdrawal.