Sahih al-Bukhari, Volume 7, Book 62, Hadith 7 (USC-MSA)

Narrated Sa`id bin Jubair: Ibn `Abbas asked me, "Are you married?" I replied, "No." He said, "Marry, for the best person of this (Muslim) nation (i.e., Muhammad) of all other Muslims, had the largest number of wives."

حَدَّثَنَا عَلِيُّ بْنُ الْحَكَمِ الأَنْصَارِيُّ، حَدَّثَنَا أَبُو عَوَانَةَ، عَنْ رَقَبَةَ، عَنْ طَلْحَةَ الْيَامِيِّ، عَنْ سَعِيدِ بْنِ جُبَيْرٍ، قَالَ قَالَ لِي ابْنُ عَبَّاسٍ هَلْ تَزَوَّجْتَ قُلْتُ لاَ‏.‏ قَالَ فَتَزَوَّجْ فَإِنَّ خَيْرَ هَذِهِ الأُمَّةِ أَكْثَرُهَا نِسَاءً‏.‏

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