The source of authority was transferred from public opinion to God. Bernard Lewis writes the community at Medina became a new kind of tribe with Muhammad as its sheikh, while at the same time having a religious character. Watt argues that Muhammad's authority had not extended over the entirety of Medina at this time, such that in reality he was only the religious leader of Medina, and his political influence would only become significant after the Battle of Badr in 624. Lewis opines that Muhammad's assumption of the role of statesman was a means through which the objectives of prophethood could be achieved. The constitution, although recently signed, was soon to be rendered obsolete due to the rapidly changing conditions in Medina, and with the exile of two of the Jewish tribes and the execution of the third after having been accused of breaching the terms of agreement.