 In 1132 Ayyub was in the service of Imad ad-Din Zengi.He participated in a battle against the Seljuk Sultan near Tikrit and saved Zengi's life when he assisted his retreat across the Tigris.In 1136, Shirkuh killed a Christian with whom he was quarrelling in Tikrit, and the brothers were exiled (Ayyub's son Yusuf, later known as Saladin, was supposedly born the night they left).