Imam Khomeini through his theological works explains as following:
The one who feels jealous of others and desires for the loss of a good enjoyed by another and harbors spite against those who possess it in his heart, should know that he does not believe that it is in his own interest that God Almighty has not bestowed upon him that favor.
Our limited understanding fails to comprehend the wisdom of His determinations. He should realize that he does not have faith in Divine Justice and the justness of His apportioning.
Verbally he may declare his belief in the doctrine of Divine Justice.
But his declaration is mere words; for the belief in the justness of God is contrary to envy.
If you deem Him just, then consider His ordainment to be just too, for the hadith says expressly that the envious man is resentful at God’s apportioning of gifts among His creatures and indignant at the favors conferred by Him.
In accordance with the Divine instincts inherent in him, man by nature is a lover of justice. Modesty and reverence before justice and hatred and rebellion before injustice are rooted in his nature.
However, if an opposite attitude is observed, it is because of a defect in his premises.
If he is indignant at the advantages enjoyed by others and is contentious about the Divine apportioning of bounties, it is on account of the fact that lie does not consider it as just, but, God forbid, regards it as unjust and cruel.
It is not because he considers the Divine apportioning as just and is yet resentful of it. It is not that he considers the Divine plan to be a perfect system and absolutely good and yet is displeased with it, Imam further expalains.
Alas, our faith is not complete and the intellectual proofs have not crossed the limits of reason and intellect to enter the realm of the heart. Faith is not [solely] a matter of utterance.
It is not mere reading, discussing, or quoting others; it requires sincerity of intention.
One who seeks God succeeds in finding Him. Those who are interested in Divine knowledge, seek it.
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