Ja'fari jurisprudence

Jaʿfari jurisprudence, Jaʿfari school of thought, Jaʿfarite School, or Jaʿfari Fiqh is the school of jurisprudence of most Shia Muslims, derived from the name of Ja'far al-Sadiq, the 6th Shia Imam. This school of jurisprudence is followed by Twelvers in general and Isma'ilis in part, as well as a small minority of Zaidis.

It differs from the four or sometimes Five Schools or madhhabs of Sunni jurisprudence in its reliance on ijtihad, as well as on matters of inheritance, religious taxes, commerce, personal status, and the allowing of temporary marriage or mutʿa. However, despite these differences, there have been numerous fatwas regarding the acceptance of Jaʿfari fiqh as an acceptable Muslim madhhab by Sunni religious bodies. These include the Amman Message and a fatwa by Al-Azhar. In the modern era, former Prime Minister of Sudan Sadiq al-Mahdi defined the recognized schools of Muslim jurisprudence as eight, Ja'fari was one of them. While many differences between Ja'fari fiqh and that of Sunni Muslims are minor, a notable difference being that Ja'fari jurisprudence allows temporary marriage in the form of Nikah mut‘ah, while Sunni Islamic Law allows for temporary marriage in the form of Nikah Misyar and Nikah 'urfi.

This school of thought utilizes ijtihad by adopting reasoned argumentation in finding the laws of Islam. Usulis emphasize the role of Mujtahid who was capable of independently interpreting the sacred sources as an intermediary of the Hidden Imam^as and thus serve as a guide to the community. This meant that legal interpretations were kept flexible to take account of changing conditions and the dynamics of the times. This school of thought is predominant among most Shia.

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