Muhammad al-Baqir (Arabic: ???????? ??????????) full name Muhammad bin 'Ali bin al-Husayn bin Ali bin Abi Talib, also known as Abu Ja'far or simply al-Baqir ("the one who opens knowledge") (677-733) was the fifth Shia Imam, succeeding his father Zayn al-Abidin and succeeded by his son Ja'far al-Sadiq.
He was the first Imam descended from both grandsons of Muhammad: Hasan ibn Ali and Husayn ibn Ali.
He is revered by Shiite Muslims for his religious leadership, and respected by Sunni Muslims for his knowledge and Islamic scholarship as a jurist in Medina.