Mohamed Sayed Tantawi was the Grand Imam of al-Azhar Mosque and Grand Sheikh of al-Azhar University.
Tantawi joined the Alexandria Religious Institute in 1944, and became a member of the faculty of Ausol Aldeen in 1968. In 1972 he became a member of the faculty of Arabic & Islamic Studies at the Islamic University of Libya. In 1980 he moved to Saudi Arabia, where he became chief of the Tafsir branch of the Postgraduate studies branch at the Islamic University of Madinah. He returned to Egypt in 1985, when he became Dean of the Faculty of Ausol Aldeen at the prestigious Alexandria Religious Institute.
In 1986 Tantawi was appointed as Grand Mufti of Egypt on his 58th birthday, 28 October 1986. He held this position for almost ten years, until he was appointed Grand Imam of Al-Azhar Mosque and Grand Sheikh of Al-Azhar University by the President of Egypt, Hosni Mubarak, on 27 March 1996. The Al-Azhar Mosque is one of the most influential and important Sunni Muslim institutions.
Tantawi completed a seven thousand page exegesis of the Qur'an (Al-tafser al-waset). This Tafsir took over ten years to complete. He has also written Bano Israel (The Children of Israel) and Muamlat Al-bank (Bank's Dealings)
Tantawi led the funeral prayers at the funeral of Yasser Arafat in 2004, during which he said that "Arafat has done his duty as a defender of the Palestinian cause, with courage and honesty".
During the controversy of the French headscarf ban in schools, he issued a fatwa allowing Muslim girls to take off their headscarves while attending school, using the lesser of two evils principle.
He has issued a fatwa which allowed abortion in cases, where a