In reality Islam in its very essence has tolerance written on its brow: "Let there be no compulsion in religion (Qur'an 2:257)"; "But if thy Lord had pleased, verily all who are in the earth would have believed together. What! wilt thou compel men to become believers? No soul can believe but by the permission of God." "We know best what the infidels say: and thou art not to compel them. Warn then by the Qur'an those who fear my menace." Thus did Muhammad teach his people, to whom he himself was also an example of gentleness and forbearance in the manner he treated his defeated opponents. "On the triumphal march to Mecca, leading an army of believers intoxicated by the consciousness of a power now irresistible, the Prophet was riding with bowed head in humble thankfulness for the grace of Allah had granted him, and whenever he was victorious he was able to show humane and magnanimous qualities"; this is Gabrieli's opinion, and Tor Andrae himself admits that "it is rarely that a victor has exploited his victory with greater self-restraint and forbearance than did Muhammad". The followers of other revealed religions were not forced to become Muslims. The Qur'an contains the following instruction as to how to treat them: "Verily, they who believe, and the Jews, and the Sabeites, and the Christian-- whoever of them believeth in God and the last day, and doth what is right, on them shall come no fear, neither shall they be put to grief."