What is the ruling on profits resulting from projects in which money, part of which was acquired through unlawful means before repentance, was invested, and is it permissible for a Muslim to benefit from these profits after sincere repentance?

To repent from illicitly gained money, one must return stolen goods and rights to their owners, exerting every possible effort. As for the profit generated from investing illicit money, scholars have differed on this matter. Some are of the view that it belongs to the worker, based on the Prophet’s (peace be upon him) saying: "The gain is in proportion to the liability." Others believe that it follows the principal money. The most equitable opinion is that the profit should be divided between the capital and the labor.

If it is impossible to identify the rightful owners or reach them after exerting all effort, then the money must be given in charity with the intention that its reward goes to its owners. After disposing of the illicit money and its profits, the permissible money and its profits become pure for use and for paying zakat (definition).

The repentant person must increase in acts of righteousness and obedience to compensate for what has passed, for Allah Almighty says: "Indeed, good deeds do away with evil deeds," and the Prophet (peace be upon him) said: "Follow up a bad deed with a good deed that will erase it."

Allah gives glad tidings to the repentant, saying: "Except for those who repent, believe and do righteous work. For them Allah will replace their evil deeds with good deeds," and "Say, 'O My servants who have transgressed against themselves [by sinning], do not despair of the mercy of Allah.'"