As We sent to you an Apostle from among yourselves, who recites to you Our signs, and purifies you, and teaches you the Book and wisdom, and teaches you what you did not know. (2:151)
Purifying one’s heart is a critically important matter for all believers, as the Qur’an and teachings of our Prophet ﷺ (peace be upon him) emphasize, but for one traveling the path of sacred knowledge it is an even more crucial endeavor. This is because the state of one’s heart has a very real effect on how one perceives knowledge and how it manifests in one’s deeds. When one’s heart is sound, knowledge can be absorbed and understood properly and enlighten and illuminate one’s inner state. It then has a positive and meaningful effect on one’s intellect and limbs, such that it can bring benefit to oneself and others. This is perhaps one of the reasons why everything on earth—even the ants in their hills and the fish in the sea—prays for the religious scholar, as a prophetic tradition teaches1 . The benefit of their knowledge has far-reaching effects and touches them all.
On the other hand, when one’s heart is not sound and is plagued by spiritual ailments, the knowledge one attains can actually bring about serious harm. It can become an obstacle that blocks and impedes one’s path to Allah subhanahu wa ta`ala (exalted is He) in various ways, and can hurt others if that knowledge is misinterpreted, misapplied or misused. These abuses of knowledge are often done on an unconscious level, the spiritual causes of which—related to the heart—are often overlooked.
The spiritual heart has been likened to a mirror. If a mirror has not been polished and contains certain blemishes and distortions, it will reflect objects in a faulty and distorted way. The reflection will be in accordance to the state of the mirror, and not the reality of the object itself. In the same way, spiritual ailments and contaminants that plague and darken the heart, disconnecting it from Allah (swt) and occupying it with negative characteristics, can mar and distort one’s perceptions of knowledge and one’s ability to distinguish between truth and falsehood, good and bad, and beauty and ugliness.
It is for this reason that one must couple one’s devotion to the Islamic sciences with a deep commitment to the spiritual purification and nourishment of one’s heart. Imam Nawawi advised, “Purify your hearts (for knowledge) the way land is purified for cultivation.” And the great scholar and tabi`i (follower) Uways al-Qarni said succinctly, “Keep watch over your heart.” (“Alayka bi qalbik.”)