Gifts of Knowledge

Shaikh ʿUthaimīn, Allaah have mercy on him, said, “This ḥadīth confirms judgement on the Day of Resurrection, that it is true and that every wronged person will be given his due right. But there is an issue here where if a person goes to someone he had oppressed in the past by backbiting him and slandering him or something of the sort, and then asks him to forgive him after he has repented to Allah and has become regretful and thus says to the person he wronged, ‘Forgive me, I was wrong, and I seek forgiveness from Allaah now and turn to Him in repentance, forgive me,’ and he apologises but the person who was wronged doesn’t accept it. So here we say that if Allaah sees that he is sincere in his repentance [/that his repentance is sound by having fulfilled its conditions] then Allaah will take on the responsibility of fulfilling the rights of that person who refused to forgive him.

The same goes for [matters related] to money. If you had an argument with someone and denied him some money of his which you had, then later you repented to Allaah and admitted it and went to him and said, ‘I denied you your right but now I repent to Allaah and am remorseful, [please] take your money,’ but he replies by saying, ‘Between me and you is the Day of Judgement,’ so here we say that if Allaah knows that your intention is true in your repentance, then He will take on the responsibility of the sin—i.e., He will satisfy the person you wronged. But you give the money away in charity on behalf of that wronged person so that you free yourself from the obligation you have to him.

For example, if you owed him 100 riyāls and you came to him after having become remorseful and having sought Allaah’s Forgiveness and asked him to take the hundred riyāls but he refused and said, ‘No, I want them from your good deeds on the Day of Judgement,’ then here we say that if Allaah sees that you are truthful in your intention then you will not be held as sinful and the sin is removed from you—but give the 100 in charity on his behalf so as to free yourself from it.
Sharḥ Riyāḍ aṣ-Ṣāliḥīn, 6/659-660.