Imam Khomeini explains the matter through his famous book of "Combat with the self" as following:
If a man had faith in God, the Exalted, and if he saw God Almighty with the eyes of his heart as one sees the sun, it would not be possible for him to commit a sin, just as if he were standing before an armed power, he would find some ‘impeccability’.
This fear comes from committing sin. The Impeccable, [ma‘sumin], peace be with them, after their creation from pure clay, because of the effects of their spiritual discipline, and acquisition of radiance and virtuous character traits, always see themselves as being in the presence of God, who knows all things and encompasses all affairs.
They have faith in the meaning of the words, “La ilaha illallah” [There is no god but Allah], and they believe that other than God, all persons and all things are perishing and have no role in determining man’s destiny, Imam further explains.
“All things are perishing but His Face” (Q28:88).
If man is certain and has faith that all the outward and inward worlds are in the presence of the Lord, and that God, the Exalted, is present everywhere and sees everything, in the presence of God and God’s blessings there would be no possibility for committing sins.
Man is not able to commit sins before a discerning child, and he does not expose his private parts; so how could he expose his private parts before God, the Exalted, and not dread to commit a crime?
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