For a number of reasons, this is a very important time to be writing a book of this nature. First, the concept of purification of the soul as a whole is and always will be central to the message of Islam and to the welfare of humans, both in this life and the Hereafter. Indeed, it was a main mission of the messengers and prophets themselves. Second, there is a very strong need to shed light on the correct path of purification as delineated by the Quran and Sunnah- free of the foreign influence, deviations and heresies that have found their way into the realm of the religion and have caused a great deal of harm. The path described by the Quran and Sunnah is the only path that can result in a true purification of the soul. Indeed, it is the only path that is truly consistent with the purpose for which humans were created. Hence, any discussion of purification of the soul must rely heavily and exclusively on the Quran and Sunnah and what can be correctly derived from those two sources. Third, many Muslims themselves are today being influenced by secular, materialistic psychology, leading them to neglect the spiritual side of humans and to ignore the guidance that Islam offers for the purification of the soul. This influence often occurs at a level wherein the person himself may not be completely aware that it is occurring. Fourth, for some time now, there has been an Islamic revival spreading throughout the Muslim world. Upon closer inspection, it seems that this revival is somewhat tenuous and delicate, in the sense that for many Muslims it is more of an µemotional ¦ phenomenon. In order for this revival to be truly successful and lead to what it needs to lead to, it must be guided by the comprehensive teachings of Islam. First and foremost among those teachings is what is related to the purification of the soul. Without the purification of the souls, the revival will only be on the outer shell and will, in fact, be a deceptive revival, in the sense that the inner consciousness will not have been reformed and the lapse back to the pre-revival times may be very close at hand. Indeed, without the purifications of the souls, the very goals of the revival from the outset may be wrong.