ভূমিকা
Alif Lam mīm (1). This Book, there is no doubt in it, (is) a guidance to those who guard (against evil) (2), Those who believe in the unseen and keep up the prayer and spend (benevolently) out of what We have given them (3), And who believe in that which has been sent down to thee and that which was sent down before thee and they are sure of the hereafter (4). These are on a guidance from their Lord and these it is that shall be the successful ones (5).
General Comment This chapter was revealed piecemeal; therefore, it does not have a single theme. However a major part of it shows a general objective: It emphasizes that a man cannot be a true servant of Allah unless he believes in all that was revealed to the apostles of Allah without making any difference between revelation and revelation, or between apostle and apostle; accordingly, it admonishes and condemns the disbelievers, the hypocrites and the people of the book because they differed about the religion of Allah and differentiated between His apostles; thereafter it ordains various important laws, like change of the direction to which the Muslims were to turn for their prayers, regulations of hajj, inheritance and fasting and so on.
Commentary Qur’an: Alif lam mīm : God willing, we shall describe in the 42nd chapter some things related to the “letter-symbols” that come at the beginning of some chapters. Also, the meaning of the guidance of the Qur'an and of its being a book will be explained later on. Qur’an: This Book, there is no doubt in it, (is) guidance to those who guard (against evil), those who believe in the unseen: Those who guard against evil, or in other words, the pious ones, are the very people who believe.
Piety, or guarding oneself against evil, is not a special virtue of any particular group of the believers.