A second period in the history of the development of Islam begins in Medina. But however brilliantly and successfully Mohammed’s prophetic labours might continue from this time forward, his character during the period of his fortune was less spotless, his conviction less sincere, his motives less pure than in the dark and suffering time of persecution and oppression. His revelations, which he received from the angel Gabriel as occasion arose, were circulated as inspired sayings amongst the people, partly through oral tradition, partly in fly-leaves until they were put together in one whole as the holy writing (_Koran_). They were not drawn up without occasional adjustment to the circumstances of the moment and to his own appetites, a transformation which reveals itself even in the form and the language. For whilst in the parts drawn up in Mecca poetic enthusiasm prevails to an undue extent, in Medina the oratorical element is more in the foreground; for Mohammed, all too closely bound to material things, was no longer able to disengage himself from them. In the lack of personal conviction which now supervened, if he wished to rise above the commonplace he had to supply the inner impulse by affected vividness, and the truth firmly believed by empty sophistry; and from his manner of writing it is easy to see that his thoughts no longer spring from a warm heart, but are the products of a cold intellect. No longer following the suggestions of his mind can he allow his discourse to pursue its natural course; all must now be thought out beforehand, for it is no longer guided by the spirit of God but by his own _ego_. The first mosque, a simple, artless building made of the wood of date trees, which was erected soon after his arrival in Medina, became a sacred centre of his teaching. From its roof, five times each day, the steadfast devotee Bilal summoned the faithful to prayer. [Illustration: ARAB CHIEF IN THE TIME OF MOHAMMED]