“When belief in “La ilaha illa Allah” penetrates into the deep recesses of the heart, it also penetrates through the whole system of life, which is a practical interpretation of this faith. By this means, those who believe are already pleased with the system which this faith uniquely determines and submit in principle to all the laws and injunctions and details even before they are declared. Indeed the spirit of submission is the first requirement of the faith. Through this spirit of submission the believers learn the Islamic regulations and laws with eagerness and pleasure. As soon as a command is given, the heads are bowed, and nothing more is required for its implementation except to hear it. In this manner, drinking was forbidden, usury was prohibited, and gambling was proscribed, and all the habits of the Days of Ignorance were abolished – by a few verses of the Qur’an or by a few words from the lips of the Prophet. Compare this with the efforts of secular governments. At every stage they have to rely on legislation, administrative institutions, police and military power, propaganda and the press, and yet they can at most control what is done publicly, and society remains full of illegal and forbidden things.”
[Sayyid Qutb (R) in the chapter, “The Nature of the Quranic Method” of his book , Milestones, pp. 45-46].