Sin, penetrating to the heart, will blacken and darken it until it extinguishes the light of faith. Within each sin is a path leading to unbelief. Unless that sin is swiftly obliterated by seeking God's pardon, it will grow from a worm into a snake that gnaws on the heart.

For example, a man who secretly commits a shameful sin will fear the disgrace that results if others become aware of it. Thus the existence of angels and spirit beings will be hard for him to endure, and he will long to deny it, even on the strength of the slightest indication.

Similarly, one who commits a major sin deserv­ing of the torment of Hell, wil! desire the non­existence of Hell wholeheartedly, and whenever he hears of the threat of Hell-fire, he will dare to deny it on the strength of a slight indication and doubt, unless he takes up in protection the shield of repentance and seeking forgiveness.

Similarly, one who does not perform the obligatory prayer and fulfil his duty of worship will be affected by distress, just as he would be in case of the neglect of a minor duty toward some petty ruler. His laziness in fulfulling his obliga­tion, despite the repeated commands of the Sove­reign of Pre-Eternity, will distress him greatly, and on account of that distress will desire and say to himslef: "Would that there were no such duty of worship!" In turn, there will arise from this desire a desire to deny God. and bear enmity toward Him. If some doubt concerning the existence of the Divine Being comes to his heart, he will be inclined to embrace it like a conclusive proof. A wide gate to destruction will be opened in front of him. The wretch does not know that although he is delivered by denial from the slight trouble of duty of worship, he has made himself, by that same denial, the target for millions of troubles that are far more awesome. Fleeing from the bite of a gnat, he welcomes the bite of the snake.

There are many other examples, which may be understood with reference to these three, so that the sense of.

Nay but their hearts are stained¹  will become apparent.

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2. Qur"an, 83:1