Tajdid
The tradition of a renewal of the faith went back to Islam's first century, with the caliph Umar II ('Umar ibn 'Abd al-'Aziz), who came to power in the Muslim year 99 and was particularly revered for his piety, in contrast to his predecessors. He was viewed as a renewer of the faith in an age of increasingly profane rule, and later mujaddids and their movements in various parts of the Islamic world followed his precedent.