The best teachings in the Koran are borrowed from the Bible or the Talmud. In consequence of the difficulties which Mahomet for several years (612-633) had to encounter in Mecca on account of these purified doctrines, there grew around the sound kernel a loathsome husk. Mahomet's connection with the Jews of Arabia assisted not a little in determining and modifying the teachings of Islam. Portions of the Koran are devoted to them, at times in a friendly, at times in a hostile spirit. When Mahomet failed in obtaining a hearing in Mecca, the seat of idolatrous worship in Arabia, and even ran the risk of losing his life there, he addressed himself to some men from Yathrib, and urged them to accept his doctrines. These men were more familiar with Jewish doctrines than the Meccans; they found in Mahomet's revelations a close analogy to what they had often heard from their Jewish neighbors. They, therefore, showed themselves inclined to follow him, and caused him to be invited to Yathrib, where his teachings were likely to be favorably received on account of the numerous Jews residing there. As soon as he came there (622, the year of expatriation--Hejira), Mahomet took care to win over the Jews of Yathrib and to set forth his aims, as though he desired to bring about the universal recognition of Judaism in Arabia. When he saw the Jews fasting on the day of Atonement, he said, "It becomes us more than Jews to fast on this day," and he established a fast-day (Ashura). Mahomet entered into a formal alliance for mutual defense with the Jewish tribes, and instituted the custom of turning towards Jerusalem in prayer (Kiblah). In the disputes between the Jews and his disciples (Moslems), which were submitted to his judgment, he behaved leniently to the Jews. For this reason Mahomet's disciples preferred to bring the matters in dispute before a Jewish chief, because they expected more impartiality from him than from Mahomet. Mahomet for a long time employed a Jewish scribe to do his correspondence, he himself being unable to write. These advances on the part of a man of so much promise were very flattering to the Jews of Medina. They looked upon him to some extent as a Jewish proselyte, and expected to see Judaism through him attain to power in Arabia. Some of them followed him devotedly and were his faithful allies (Ansar); amongst them was a learned youth, Abdallah Ibn-Salâm, of the race of Kainukaa. Abdallah and other Jews assisted Mahomet in propagating the Koran. The unbelieving Arabs frequently reproached him, saying that he was an ear (accepted anything as truth), that it was not the angel Gabriel who was teaching him, but a mortal man. Nevertheless, though Abdallah Ibn-Salâm and other Jewish Ansars supported him, they were far from abandoning Judaism on this account, and continued to observe the Jewish commandments, and Mahomet was at first not offended by this conduct.