عَنْ سَفِينَةَ أَبِي عَبْدِ الرَّحْمَنِ رَضِيَ اللَّهُ عَنْهُ قَالَ أَعْتَقَتْنِي أُمُّ سَلَمَةَ رَضِيَ اللَّهُ عَنْهَا وَاشْتَرَطَتْ عَلَيَّ أَنْ أَخْدُمَ النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ مَا عَاشَ
It is narrated from Abu Abdur Rahman Sayyiduna Safina (may Allah be pleased with him), who says: Umm al-Mu'mineen Sayyida Umm Salama (may Allah be pleased with her) set me free and placed this condition upon me that as long as the Noble Prophet (peace and blessings be upon him) is alive, I will continue to serve him.