"It is most important to spend one's time and energy in treating the heart and hastening to correct and purify if from sickness and all sins. This is due to the heart occupying a great and lofty position in Islam; it is indeed the place to which the Lord looks and the storehouse for tawheed, faith and sincerity. Actions are distinguished, one from the other, with respect to their excellence in the Sight of Allah in accordance with the condition of the heart, not by their number or form, but rather due to the strength of the caller, his truthfulness, his sincerity and the extent to which he prefers Allah over himself..." Taken from the Compiler's Foreword.