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bukhari:7208Abū ʿĀṣim > Yazīd b. Abū ʿUbayd > Salamah

We gave the oath of allegiance to the Prophet ﷺ under the tree. He said to me, "O Salama! Will you not give the oath of allegiance?" I replied, "O Messenger of Allah ﷺ! I have already given the oath of allegiance for the first time." He said, (Give it again) for the second time.  

البخاري:٧٢٠٨حَدَّثَنَا أَبُو عَاصِمٍ عَنْ يَزِيدَ بْنِ أَبِي عُبَيْدٍ عَنْ سَلَمَةَ قَالَ

بَايَعْنَا النَّبِيَّ ﷺ تَحْتَ الشَّجَرَةِ فَقَالَ لِي يَا سَلَمَةُ أَلاَ تُبَايِعُ قُلْتُ يَا رَسُولَ اللَّهِ قَدْ بَايَعْتُ فِي الأَوَّلِ قَالَ وَفِي الثَّانِي