The Father of Greatness (Syriac Abā d-Rabbūtā) is the supreme deity of Manichaeism, the wholly good and uncreated God who dwells in eternal repose in the Realm of Light together with his aeons. He is one of the two co-eternal first principles of the dualist system, opposed by the King of Darkness. The Father does not himself descend into the cosmic conflict; instead, when Darkness assaults the borders of Light, he initiates the drama through a graded sequence of evocations, calling forth the Mother of Life, the Living Spirit, and the Third Messenger in three successive 'creations'. In the Iranian-language texts his name is rendered literally as pīd ī wuzurgīh or, adopting Zoroastrian dress, equated with the high god Zurwān; in the Coptic and Greek sources of the Roman west he is the Father of Greatness or Father of Lights.