Imam Khomeini in his famous work of "the combat with the self" explains the matter as following:
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,
“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?
This is because he has faith in the presence of the child, however, with regard to the divine presence, if he has knowledge, he still lacks faith.
Due to the multiplicity of his sins which have darkened and blackened his heart, he is totally unable to accept such truths, and may not even consider them to be likely.
Actually, man would not recklessly run wild if he considered it all likely, he need not have certainty, that which is reported in the Noble Qur’an is right, the promises and the threats, and that he should amend his ways and deeds, Imam further explained.
If you consider it all likely that ferocious beasts are to be found along the path which might harm you, or that there are armed bandits who might hold you up, you would refrain from taking that path, and you would try to ascertain the correctness or incorrectness of these reports.
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