In Sunni tradition, the title was used exclusively for the scholar al-Ghazali, due to his influential integration of Sufism and sharia. However, there is some evidence of application of the term to later Sunni scholars, in imitaion of the Shia usage.
In TwelverShia the title is awarded to scholars. It was originally applied as an honorific to leading scholars, but now the use indicates a status in the hierarchy of the learned below Ayatollah. It is divided into two sub ranks, Hujjatu l-Islām wa l-Muslimīn ("Authority on Islam and Muslims") and Hujjatu l-Islām ("Authority on Islam"), given to middle-ranking clerics.