[2] When Saladin became vizier of the Fatimid Caliphate, Najm al-Din rose in his favour and became his close friend and advisor.
[1][2] He was among the chief proponents of a juridical opinion that urged Saladin to depose and even execute the last Fatimid caliph, al-Adid, on account of his heretical beliefs and those of his family.
[3][2] On Najm al-Din's advice, Saladin opened a Shafi'i law college in the area of al-Qarafah, next to the tomb of the school's founder, al-Shafi'i.
[1][2] His fame exceeded Egypt and reached even al-Andalus, as the Andalusi traveller Ibn Jubayr went to receive his blessing during his visit to Fustat.
[4] Najm al-Din died on 12 Dhu'l-Qa'dah 587 AH (1 December 1191) and was buried at the foot of the tomb of al-Shafi'i.