Hadith.3341 - The Messenger of Allah سبحانه وتعالى, peace and blessings be upon him and his family, said: "Whoever swears to you by Allah سبحانه وتعالى regarding a right, then believe him, and whoever asks you in the name of Allah سبحانه وتعالى, then give him. The oath is for the claimant, and there is no claim for him without it."
The compiler of this book, may Allah سبحانه وتعالى have mercy on him, commented:
Whenever a man who had taken an oath on a right repents and returns what he owes, along with the profit he gained from it, the rightful owner should take back his principal amount and half of the profit, and return the other half of the profit to the repentant man, because he is a repentant person.
This was narrated by Misma' Abu Sayyar from Abu Abdullah عليه السلام, and I will mention the full wording of this narration later in this book, in the chapter on deposits (al-wadi'ah), if Allah سبحانه وتعالى, the Exalted, wills.