Imamexplains the matter in his famous book "an exposition on Forty Hadith" as following:
Sometimes they are so subtle that one is not aware of them as suspect wiles of Satan and of the self, unless he is made conscious and waken up. With all their variety, all of them work together in obstructing people from the Divine path and deviating them from it.
Their grades are various. There are the victims of desire who take gold and wealth and the like to be their god; there are others about whom Almighty God informs us in these words:
Hast thou seen him who has taken his desire (hawa) to be his god? (25:43)
Again, there are those who, according to the holy tradition under discussion, are alienated from God by following the desires of the self and the fabrications of the Devil, in the form of false creeds, corrupt norms or something else.
There are the perpetrators of mortal and major or minor and venial sins who are kept from the path of God in a measure proportional to the degree of their transgressions.
Then there are the followers of legitimate pleasures and desires who, on account of their overindulgence in them, are kept back from treading the Divine path in a different way.
There are the devout given to prayers and formal rites, which are aimed to secure a good life in the Hereafter or to satisfy some worldly purpose or are meant to secure higher spiritual stations or to avoid spiritual decline, who are prevented from the path of God in a different way, Imam further explains.
There are the practitioners of ethics devoted to purification of the soul and spiritual disciplining for the sake of attaining self control or reaching the paradise of moral excellence, who are kept from God and righteousness in their own manner.
There are the practitioners of ‘irfan, the wayfarers of the Path, the seekers of ecstasies and of mystic stations and states, who have no other purpose except His vision and His vicinity, yet whose vision is obstructed in a different way and are kept from receiving the special illuminations.
Besides, there are other stages whose description is not possible here.
Thus it is necessary for every individual, in accordance with the category to which he belongs, to examine his own condition and purge himself of the desires of the self in order not to be kept from the path of righteousness and of truth, so that the doors of compassion and benevolence are opened to him, whatever his station and stage.
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