"The total religion called Islam may be said to consist of the levels of islam, iman, and ihsan, or surrender, faith, and spiritual beauty. The Quran refers often to the muslim, the possessor of surrender, the mu’min, the possessor of faith, and the muhsin, the possessor of virtue. Although the Quran emphasizes that all Muslims stand equally before God, it also insists that human beings are distinguished in rank according to their knowledge of the truth and virtue, as in the verses, “Are those who know equal with those who know not?” (39:9), to which the Quran gives the resounding answer of no, and, “Verily, those of you most close to God are those who are the best in conduct” (59:13)."