Imam Khomeini in his famous work "the combat against the self expalins as following:
You should know that with His Wisdom and Authority, God Almighty has created certain powers and faculties in the invisible world of the inner self. They are of enormous benefits for us. Here we shall mention three of them: they are, al-quwwah al-wahmiyyah-the power of invention or imagination, al-quwwah al-ghadabiyyah-the power of passion or anger, and al-quwwah al-shahwiyyah-the power of lust or sensuality.
Each of these powers is of great benefit to the mankind, like the preservation of the human individual and species, advancement of human interests in this world as well as in the Hereafter, of which religious scholars have given elaborate accounts and I need not repeat them.
What is essential to state here is that these three powers are the source and origin of all virtuous and vicious deeds, and the source of all invisible and sublime forms.
Briefly speaking, as man possesses a physical and a terrestrial form in this world, which is devised and contrived by the Almighty in such a wonderful manner that all great philosophers and scientists are puzzled, and the science of anatomy is not fully equipped to discover and understand its functioning rightly even to this day.
God has made man superior to other living beings by endowing him a superb constitution and a beautiful appearance. Yet there is another form and a different face of him, which is heavenly and invisible, which is determined by the qualities of his soul and his inner nature.
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