Religion is as natural to man as social intercourse. The aim common to the religions of the world is that they undertake to bestow upon mankind the highest blessings, and the special way in which they seek to accomplish this is by establishing friendly relations with a Power which is stronger than the ordinary course of nature. Every religion which has counted for anything has had ready answers to three questions: What does it promise to do for the good of man? What is the nature of the higher Power on whose succor it relies? And, what is required of man as the condition of receiving the expected benefits? A further working test of its value is what it makes of morality.
For Christianity, the appropriate question is "What do Christians believe?" In contrast, for Islam, the correct question is "What do Muslims do?" Whereas in Christianity, theology was the "queen of sciences," in Islam, law enjoyed pride of place, for "to accept or conform to the laws of god is Islam, which means to surrender to God's law."
Because Islam means surrender or submission to the will of God, Muslims have tended to place primary emphasis on obeying or following God's will as set forth in Islamic law. For this reason, many commentators have distinguished between Christianity's emphasis on orthodoxy, or correct doctrine or belief, and Islam's insistence on orthopraxy, or correct action. However, the emphasis on practice has not precluded the importance of faith or belief. Faith and right action or practice are intertwined.
As the confession of faith or basic creed ("There is no god but God and Mohammed is the messenger of God") illustrates, faith in God and the Prophet is the basis of Muslim belief and practice. As the primary source of God's revelation and law, the Quran is the sourcebook of Islamic principles and values. Although the Quran declares, "Here is a plain statement to men, a guidance and instruction to those who fear God," it does not constitute a comprehensive code of laws. While it does contain legal prescriptions, the bulk of the Quran consists of broad and general moral directives- what Muslims ought to do. It replaced, modified, or supplemented earlier tribal laws. Practices such as female infanticide, exploitation of the poor, usury, murder, false contracts, fornication, adultery, and theft were condemned. In other cases, Arab customs were gradually replaced by Islamic standards. Quranic prescriptions governing alcohol and gambling illustrate this process. At first, the use of alcohol and gambling had not been expressly prohibited. However, over a period of years, a series of revelations progressively discouraged their use. The first prescription against the old custom is given in the form of advice: "They ask thee concerning wine and gambling. Say: in them is great sin and some use for man; but the sin is greater than the usefulness." Then, Muslims were prohibited from praying under the influence of alcohol: "Approach not prayer with a...