Qatadah said concerning this verse: "And let not those among you who are endowed with grace and means swear" up to "the poor" [Surah al-Nur: 22], he said: Let not those among you who are endowed with grace and means swear that they will give to relatives, up to "Forgiving, Merciful" [Surah al-Baqarah: 173]. This verse was revealed about a man of Quraysh called Mistah, who was related to Sayyiduna Abu Bakr (may Allah be pleased with him) and was an orphan under his guardianship, and he was among those who spread about Sayyidah Aishah what they spread. When Allah revealed her innocence and her vindication, Sayyiduna Abu Bakr (may Allah be pleased with him) swore that he would not give him any benefit. So it was said to him: Do you not love that Allah should forgive you? He said: Yes indeed. It was said: Then pardon and overlook. Sayyiduna Abu Bakr (may Allah be pleased with him) said: Certainly, I will not withhold from him the kindness I used to show him before this.
Hadith Referenceالمعجم الكبير للطبراني / مسند النساء / 19528