Abu l-Ḥasan ʿAlī b. Muḥammad al-Hādī, (b. 212/828 – d. 254/868) was the son of Imam al-Jawad (a) and he was the tenth of the twelve Imams of the Shia. He is also known as al-Naqī (النقي, the pure) and al-Hādī (الهادي, the guide). He was the Imam (leader) between 220/835 and 254/868 for a period of thirty-four years.
Many years of the imamate (leadership) of Imam al-Hadi (a) took place in Samarra under direct surveillance of the rulers of his time. His imamate was contemporary with the rule of some Abbasid caliphs including al-Mutawakkil al-‘Abbasi.
Different hadiths are narrated from Imam al-Hadi (a) about ideological issues, interpretation of the Qur’an, fiqh, and ethics. Al-Ziyarah al-Jami’a al-Kabira which includes Shi’a ideological concepts about the Imams, is narrated from Imam al-Hadi (a).