وَعَنْ سَفِينَةَ رضى الله عنه
«قَالَ: كُنْتُ مَمْلُوكًا لِأُمِّ سَلَمَةَ فَقَالَتْ: أُعْتِقُكَ، وَأَشْتَرِطُ عَلَيْكَ أَنْ تَخْدِمَ رَسُولَ اَللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: مَا عِشْتَ»
‘I was a slave of Umm Salamah and she said, ‘I shall emancipate you, but on the condition that you serve the Messenger of Allah (sallallahu alayhi wa sallam) as long as you live.’ Related by Ahmad, Abu Dawud, An-Nasai and Al-Hakim.’