Ovadia Yosef and Pikuach Nefesh

Despite his controversial public comments, Ovadia Yosef had long been a distinguished rabbinical authority advocating peace negotiations in the Israeli–Palestinian conflict, and had done so since the late 1980s. His main justification was the halakhic principle of Pikuach Nefesh, in which all the Jewish commandments (excluding adultery, idolatry, and murder) are put on hold if a life is put in danger. Using an argument first articulated by the late American rabbinical leader Joseph Soloveitchik, Yosef claimed that the Arab–Israeli conflict endangers human lives, thereby meeting the above criteria and overruling the priority of commandments pertaining to settling the land of Israel.
Therefore, Israel is permitted—even obligated if saving lives is a definitive outcome—to make serious efforts to reach a peace settlement, as well as to make arrangements to properly protect its citizens.
Yosef first applied the Pikuach Nefesh principle to Israel’s conflicts with its neighbors in 1979, when he ruled that this argument granted Israel authority to return the Sinai Peninsula to Egypt.