Hadith 3928
حَدَّثَنَا مُسَدَّدُ بْنُ مُسَرْهَدٍ، حَدَّثَنَا سُفْيَانُ، عَنِ الزُّهْرِيِّ، عَنْ نَبْهَانَ، مُكَاتَبِ أُمِّ سَلَمَةَ قَالَ سَمِعْتُ أُمَّ سَلَمَةَ، تَقُولُ قَالَ لَنَا رَسُولُ اللَّهِ صلى الله عليه وسلم " إِنْ كَانَ لإِحْدَاكُنَّ مُكَاتَبٌ فَكَانَ عِنْدَهُ مَا يُؤَدِّي فَلْتَحْتَجِبْ مِنْهُ " .
Narrated Umm Salamah, Ummul Mu'minin:
The Messenger of Allah (ﷺ) said to us: If one of you has a slave, and he enters into an agreement to purchase his freedom, and can pay the full price, she must veil herself from him.
Reference : Sunan Abi Dawud 3928
In-book reference : Book 31, Hadith 3