—“so that He may make what Satan casts a trial for those whose hearts are diseased and whose hearts have hardened” (22:53). A heart afflicted by doubts and shallow knowledge is shaken by the slightest whisper; it is swayed, affected, and ensnared by every passing temptation.

An example of the second category is His statement in Surat al-Ahzab: “Do not be soft in speech, lest the one who has a sickness in his heart should lust after you; instead, speak in an appropriate manner” (33:32). Here the sickness is one of lust and a will inclined to immorality: the smallest cause of seduction hurls such a person into the trial, whether by mere desire or by deed. Anyone who seeks a sin that Allah has forbidden has a heart diseased with lust. Were his heart sound, he would display the qualities of the intelligent, innocent, God-fearing people described in Surat al-Hujurat: “But Allah has made faith beloved to you and has adorned it within your hearts, and He has made disbelief, debauchery, and disobedience hateful to you. Such are the rightly guided— a bounty and a favor from Allah” (49:7–8).

Whoever finds his heart in the condition Allah praises here should thank Him for a blessing unmatched by any other. He should ask Allah to keep him firm upon it and to increase him in His bounty and mercy.