Oz did his Israel Defense Forces service in the Nahal Brigade, participating in border skirmishes with Syria. After concluding his three years of mandatory regular army service, he was sent by his kibbutz to the Hebrew University of Jerusalem, where he studied philosophy and Hebrew literature. He graduated in 1963 and began teaching in the kibbutz high school, while continuing to write. He served as an army reservist in a tank unit which fought in the Sinai Peninsula during the Six-Day War, and in the Golan Heights during the Yom Kippur War.