Al-Kulaynī relates the following ḥadīth in the section on vanity in the chapter on faith and disbelief in al-Kāfī:
ʿAlī b. Ibrāhīm, from Muḥammad b. ʿĪsā b. ʿUbayd, from Yūnus, from one of our associates, from Abū ʿAbd Allāh [al-Ṣādiq], peace be upon him, who said:
The Messenger of God, God bless him and his family, said:
Once Moses, peace be upon him, was seated when Satan approached him wearing a colorful burnoose. When he got close to Moses, peace be upon him, Satan removed the burnoose and greeted him.
Moses said, “And who are you?”
He said, “I am Iblīs.”
Moses said, “You?! May God keep you away.”
Satan said, “I only came to pay my respects on account of your station before God.”
So Moses said, “Why the burnoose?”
Satan said, “I use it to steal the hearts of men.”
Moses said, “Tell me then what is the sin through which you overpower men?”
Satan said, “When he is filled with admiration for his own self, thinks he has done a great deal of good, and trivializes his sins.”
The Imam (or the Prophet) said, “God the mighty and the sublime told David, peace be upon him, to, ‘Give sinners glad tidings and warn the righteous.”
David said, “How could I give sinners glad tidings and warn the righteous?”
God said, “David, give sinners the good news that I accept repentance and forgive sin, and warn the righteous not to be vain about what they have done for if I were to settle anyone’s account, he would be doomed.”
Regarding “and warn the righteous not to be vain about what they have done,” in his commentary on al-Kāfī, al-Māzandarānī (d. 1081 AH) says:
That is, don’t be pleased with what you’ve done, don’t rely on it, and don’t ever suppose that it means you aren’t delinquent… No one could ever repay their debt to God. Anything that anyone does is deficient in comparison to God’s majesty and it is worthless in comparison to God’s blessings… Thus God’s benevolence and his requital is not a just desert, it’s simply his favor.
Regarding “is not a just desert, it’s simply his favor,” in an annotation to al-Māzandarānī’s commentary, al-Mīrzā Abū l-Ḥasan al-Shaʿrānī (d. 1393 AH) says:
According to Imāmīs and Muʿtazilīs (ahl al-ʿadl), God’s justice and wisdom entail that a person must be compensated for every hardship he suffers on account of his obedience to God—this is what reason dictates. If God were not just or wise, he might fail to do what is proper (wājib), but not if he is wise and just. If one were to argue that reason may err in such matters, the fundamental notions of God’s grace (qāʿidat al-luṭf), prophethood, the imamate, and the afterlife would all be rendered baseless.
Perhaps al-Māzandarānī meant that the just desert which a just and wise God must give us is far less than what we actually get in the afterlife. In principle, we deserve to be rewarded, but the measure of the reward we actually get far exceeds what we deserve, and God’s favor is what accounts for the difference.
Our scholars have said that a just and wise God must compensate a person—whether a believer, a disbeliever, or even an animal—for every hardship, every calamity, every pain, every disease, and every deficiency that afflicts him as long as it is from God and not from the person himself… [In fact] someone who says that a person doesn’t deserve any reward for the prerequisite of an obligation, like traveling to Mecca for the hajj, if it isn’t followed by the obligation itself (e.g., the hajj), which would be the case if he died along the way to Mecca, such a person knows nothing about the principles of our religion.
Regarding the colors of Satan’s burnoose, in Mirʾāt al-ʿuqūl, al-Majlisī II says:
The colors of the burnoose represented worldly desires and their adornment, or different religions and contrived views, or something broader in meaning…