He passed by the Prophet ﷺ, who said to him, "Maymun," or "Mahran, we are a household forbidden from accepting charity, and our freed slaves are considered as ourselves, so do not eat from charity."
أنه مر على النبي ﷺ فقال له يا ميمون أو يا مهران: إنا أهل بيت نهينا عن الصدقة وإن موالينا من أنفسنا ولا تأكل الصدقة.
Imam Ahmad narrated it (16399) from Abdul-Razzaq, and it is in his Musannaf (6942), and it was also narrated from him in Mujam al-Kabir 20/(836), from Sufyan, from Ata bin Saaib, who said, Umm Kulthum bint Ali narrated to me, he said, "I brought her a charity that he had ordered to be given," and she said, "Beware of our young men, for Maymun or Mihran..." and he mentioned the rest.Its isnad is hasan because of Umm Kulthum bint Ali bin Abu Talib, no one narrated from her except Ata bin Saaib. As for Ata bin Saaib, he became confused in his later years, but Sufyan, who is Thawri, narrated from him before that confusion set in.Haythami mentioned it in Majma al-Zawaid (3/89), attributing it to Ahmad and Tabarani, and said, "Umm Kulthum, I have not seen anyone narrate from her except Ata bin Saaib, and there is some discussion about him."I say, Umm Kulthum bint Ali bin Abu Talib here is the younger one. Ali bin Abu Talib had another daughter also called Umm Kulthum, who was the elder, whose mother was Fatimah, daughter of the Prophet ﷺ, and Umar married her and she bore him children. The younger Umm Kulthum lived a long life, and Ata bin Saaib heard from her, and her mother was an umm walad, as mentioned by Ibn Saad. This is also stated in Tajil al-Manfaah. So it seems she was known among them, except that she was not well known in the narration of hadith.Those who held that obligatory zakat is not permissible for the freed slaves of Banu Hashim relied on the apparent meaning of this hadith. But the majority of the scholars held that zakat is permissible for them, because they have no share in the portion allotted to close relatives, and the Prophet ﷺ only forbade Abu Rafi as a matter of preserving his dignity.His saying, "The mawla of a people is one of them," refers to following their example and adopting their way of avoiding what they avoid. It seems that the Prophet ﷺ used to provide for his needs, since Abu Rafi used to handle his affairs and service for him, so he conveyed to him this meaning, "If you are self-sufficient with what you have been given, then do not seek the impurities of the people, for you are our mawla and one of us." See Sharh al-Sunnah (6/103).