The martyrdom of Imam Ja'far al-Sadiq is an important religious and public holiday observed in Iran every year on the twenty-fifth day of the month of Shawwal. Imam Ja'far al-Sadiq, the sixth Shite imam, is recognized by all Shiite sects and is considered a key figure in the formulation of Shiite doctrine. He was poisoned by the Abbasid caliph al-Mansur in 765 and is buried in Medina next to his grandfather and father. The holiday commemorates his significance as a spiritual and political successor to Prophet Muhammad, and it reflects the Shia Islam state religion of Iran. During this time, various religious events are celebrated, emphasizing the importance of al-Sadiq's teachings and legacy within the Shia community.