Rabbi Ovadia Yosef, born Abdullah Youssef in Iraq in 1920, is a Talmudic scholar and recognized Halakhic authority. He is the spiritual leader of the Shas party, and former Sephardi Chief Rabbi of Israel.

Highly revered in the religious world - especially in the Sephardi and Mizrahi communities - Yosef is among the most important poskim (religious rulers) of recent generations. Yosef has been referred to as Gadol Ha'Dor (greatest of the generation), and Maor Yisrael (The Light of Israel).

From the late 1980s, Yosef has also advocated peace negotiations between Israel and its Arab neighbors. Under the halachic principle of pikuach nefesh, which states that all the Jewish commandments (excluding adultery, idolatry and murder) are nullified if a life is put in danger, Rabbi Yosef has claimed that the Arab-Israeli conflict endangers human lives. Therefore, according to Yosef, Israel is permitted, even obligated if saving lives is a definitive outcome, to make serious efforts to reach a peace settlement as well as ensure the protection of its citizens.

In 1979, amid peace negotiations between Israel and Egypt, Rabbi Yosef ruled that pikuach nefesh granted Israel authority to return the Sinai Peninsula to Egypt.
Shas, however, abstained in a vote on the first Oslo agreement with the Palestinians, and voted against the second. Furthermore, as relations between Israel and the Palestinians began to deteriorate, and specifically following the outbreak of the Second Intifada in 2001, Rabbi Yosef and Shas pulled toward the rightwing of the Israeli political spectrum, supporting the Likud. In 2005, Rabbi Yosef condemned the Gaza disengagement plan spearheaded by then-prime minister Ariel Sharon, saying that he was opposed to unilateral action outside the framework of a peace agreement. Yosef instructed the Shas MKs to vote against the plan in the Knesset.

Yosef has also made several controversial comments regarding Israeli politicians as well as world leaders. During Purim 2000, he said that then-education minister Yossi Sarid was cursed as was Haman. In 2005, Yosef commented that Ariel Sharon was “torturing” the people of Israel with his plan to disengage from the Gaza Strip. “Let God strike him down,” Yosef was quoted in a BBC article as saying at the time. However, after Sharon suffered a stroke and fell into a coma, Yosef led prayer services for his recovery, explaining that he was opposed to the disengagement plan and not to Sharon himself.

Following Hurricane Katrina in New Orleans in 2005, Rabi Yosef blamed the natural disaster on then-U.S. President Bush's support of the Gaza disengagement, as well as on the lack of Torah study among Katrina's victims, who suffered “because they have no God.”

Yosef also sparked controversy in March 2010, saying that Jews who donate their bodies for science should not be mourned. Yosef was quoted as saying, “"He who donates his body to science, to have his organs dissected, even though his intention is to advance scientific research, he is committing a serious offense, and might be relinquishing the chance of resurrection of his soul and body, and therefore we must not mourn his death.”