مُوَطَّأُ مَالِكٍ
Muwatta Malik 1269
Divorce
وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ نَافِعٍ، عَنْ صَفِيَّةَ بِنْتِ أَبِي عُبَيْدٍ، عَنْ عَائِشَةَ، وَحَفْصَةَ، زَوْجَىِ النَّبِيِّ صلى الله عليه وسلم أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " لاَ يَحِلُّ لاِمْرَأَةٍ تُؤْمِنُ
Yahya related to me from Malik from Nafi from Safiyya bint Abi Ubayd from A'isha and Hafsa, the wives of the Prophet, (ﷺ), that the Messenger of Allah, (ﷺ), said, "It is not halal for a woman in mourning for someone who has died, if she trusts in Allah and the Last Day, to abstain from adornment for more than three nights, except for a husband."
Arabic/English book reference: Book 29, Hadith 104