Sahih al-Bukhari 5064

ʿAlī narrated to us: He heard Ḥassān ibn Ibrāhīm, from Yūnus ibn Yazīd, from al-Zuhrī, who said: ʿUrwah informed me that he asked ʿĀʾishah about the words of the Exalted: ‘If you fear that you will not deal justly with orphan girls, then marry women who are good to you, two, three, or four. But if you fear that you will not be just, then one, or those whom your right hands possess. That is more likely to keep you from acting unjustly.’ She said: ‘Nephew, an orphan girl may be in the care of her guardian, who desires her wealth and beauty and wishes to marry her for less than the customary bridal gift for a woman of her standing. They were forbidden to marry such girls unless they dealt justly with them and gave them the full bridal gift, and they were commanded to marry other women instead.’