The Medinan Mosque, built with fervent hearts and anxious prayers by the Muslim and their leader, contains the embryo of all the later masterpieces of Arabian architecture—that art unique and splendid, which developed with the Islamic spirit until it culminated in the glorious temple at Delhi, whose exponents have given to the world the palaces of southern Spain, the mysterious, remote beauty of ancient Granada. In its embryo minarets and domes, its slender arches and delicate traceries, it expressed the latent poetry in the heart of Islam which the claims of Allah and the fiercely jealous worship of him had hitherto obscured; for like Jahweh of old, Allah was an exacting spirit, who suffered no emotion but worship to be lord of his people's hearts.

The Mosque was square in design, made of stone and brick, and wrought with the best skill of which they were capable. The Kibla, or direction of prayer, was towards Jerusalem, symbolic of Mahomet's desire to propitiate the Jews, and finally to unite them with his own people in a community with himself as temporal head. Opposite this was the Bab Rahmah, the Gate of Mercy, and general entrance to the holy place. Ranged round the outer wall of the Mosque were houses for the Prophet's wives and daughters, little stone buildings, of two or three rooms, almost huts, where Mahomet's household had its home—Rockeya, his daughter, and Othman, her husband; Fatima and Ali, Sawda and Ayesha, soon to be his girl-bride, and who even now showed exceeding loveliness and force of character.

Mahomet himself had no separate house, but dwelt with each of his wives in turn, favouring Ayesha most, and as his harem increased a house was added for each wife, so that his entourage was continually near him and under his surveillance. On the north side the ground was open, and there the poorer followers of Mahomet gathered, living upon the never-failing hospitality of the East and its ready generosity in the necessities of life.

As soon as the Mosque was built, organised religious life at Medina came into being. A daily service was instituted in the Mosque itself, and the heaven-sent command to prayer five times a day for every Muslim was enforced. Five times in every turn of the world Allah receives his supplicatory incense; at dawn, at noon, in the afternoon, at sunset, and at night the Muslim renders his due reverence and praise to the lord of his welfare, thanking Allah, his supreme guide and votary, for the gift of the Prophet, guide and protector of the Faithful. Lustration before prayer was instituted as symbolic of the Believers' purification of heart before entering the presence of God, and provision for the ceremony made inside the Mosque. The public service on Friday, instituted at Coba, was continued at Medina, and consisted chiefly of a sermon given by Mahomet from a pulpit, erected inside the Mosque, whose sanctity was proverbial and unassailed. Thus the seed was sown of a corporate religious life, the embryo from which the Arabian military organisation, its polity, even its social system, were to spring.

In spite of the increasing numbers of the Ansar, there still remained a party in Medina, "the Disaffected," who had not as yet accepted the Prophet or his creed. Over these Mahomet exercised a strict surveillance, in accordance with his conviction that a successful ruler leaves nothing to Providence that he can discover and regulate for himself. "Trust in God, but tie your camel." By this means, as well as by personal influence and exhortation, "Disaffected" were controlled and ultimately converted into good Muslim; for the more cautious of them—those who waited to see how events would shape—soon assured themselves of Mahomet's capacity, and the weakly passive were caught in the swirl of enthusiasm surrounding the Prophet that continually drew unto itself all conditions of men within its ever-widening circle.

Having organised his own followers, and secured their immunity from internal strife, Mahomet was forced to turn his attention to the Jewish element within his adopted city, and to decide swiftly his policy towards the three Israelite tribes who comprised the wealthier and trading population of Medina.

From the first, Mahomet's desires were in the direction of a federal union, wherein each party would follow his own faith and have control of his own tribal affairs and finances, save when the necessity of mutual protection against enemies called for a union of forces. Again Mahomet framed his policy upon the doctrine of opportunism. His ultimate aim was beyond doubt to unite both Jews and Medinans under his rule in a common religious and political bond, but he recognised the present impossibility of such action in view of the Jews' greater stability and the weakness of his party within the city. His negotiations and conciliations with the Jews offer one of the many examples of his supreme skill as a statesman.

The Jews themselves, taken almost unawares by the suddenness of Mahomet's entry into their civic life, agreed to the treaty he proposed, and acquiesced unconsciously in his subtle attempts to merge the two faiths into a whole wherein Islam would be the dominant factor. When Mahomet made Jerusalem his Kibla, or direction of prayer, and emphasised the connection between Jewish and Arabian history, they suffered these advances, and agreed to a treaty which would have formed the foundations of a political and social convergence and ultimate absorption of their own nation.

Mahomet knew that federalism with the Jews was a necessary step to his desired end, and therefore he drew up a treaty wherein mutual protection against outward enemies, as well as against internal sedition, was assured. Hospitality was to be freely rendered and demanded, and neither party was to support an Infidel against a Believer. Guarantees for mutual security were exchanged, and it was agreed that each should be free to worship in his own fashion. The treaty throws light upon the clan-system still obtaining in seventh-century Arabia. The Jews were their own masters in the ordering of their lives, as were the Medinan tribes, even after many years of neighbourhood and frequent interchange of commerce and mutual assurances. The most significant political work achieved by Mahomet, the planting of the federal, and later, the national idea in Arabia in place of the tribal one, was thus inaugurated, and throughout the development of his political power it will be seen that the struggles between himself and the surrounding peoples virtually hinged upon the acceptance or rejection of it.

The Jews, with their narrow conception of the political unit, could acquiesce neither in federalism nor in union, and as soon as Mahomet perceived their incapacity he became implacable, and either drove them forth or compelled their submission by terror and slaughter. But for the present his policy and prudence dictated compromise, and he was strong enough to achieve his will.