Hadith 15:15
Umm Salamah (RAA) narrated that The Messenger of Allah (ﷺ) said:
“When a slave of one of your women has made an agreement to pay for his freedom (i.e. he is a Mukatib) and can pay the full price, she must veil herself from him.” Related by Ahmad and the four Imams. At-Tirmidhi graded it as Sahih.
وَعَنْ أَُمِّ سَلَمَةَ -رَضِيَ اَللَّهُ عَنْهَا- قَالَتْ: قَالَ رَسُولُ اَللَّهِ - صلى الله عليه وسلم -{ إِذَا كَانَ لِإِحْدَاكُنَّ مُكَاتَبٌ, وَكَانَ عِنْدَهُ مَا يُؤَدِّي, فَلْتَحْتَجِبْ مِنْهُ } رَوَاهُ اَلْخَمْسَة ُ وَصَحَّحَهُ اَلتِّرْمِذِيّ ُ