Saints are human beings whose lives have displayed extraordinary holiness and devotion. As such they become examples for others. Indeed some of the faithful may understand them to be intermediaries and seek their help in time of need. Roman Catholics and Eastern Orthodox Christians honor saints, as do some Muslims. Though in principle Islam recognizes no mediators between human beings and God, the veneration of saints (awliya’; singular wali) is a part of popular Muslim practice. Especially in the Sufi tradition, the tombs of Sufi masters have become centers of pilgrimage.