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كتاب البيوع
34  
Sales and Trade
(49)
Chapter: What is said about markets
(49)
باب مَا ذُكِرَ فِي الأَسْوَاقِ
Sahih al-Bukhari 2120

Narrated Anas bin Malik:

While the Prophet (ﷺ) was in the market, somebody, called, "O Abul-Qasim." The Prophet (ﷺ) turned to him. The man said, "I have called to this (i.e. another man)." The Prophet (ﷺ) said, "Name yourselves by my name but not by my Kunya (name)." (In Arabic world it is the custom to call the man as the father of his eldest son, e.g. Abul-Qasim.) (See Hadith No. 737, Vol. 4)

حَدَّثَنَا آدَمُ بْنُ أَبِي إِيَاسٍ، حَدَّثَنَا شُعْبَةُ، عَنْ حُمَيْدٍ الطَّوِيلِ، عَنْ أَنَسِ بْنِ مَالِكٍ ـ رضى الله عنه ـ قَالَ كَانَ النَّبِيُّ صلى الله عليه وسلم فِي السُّوقِ، فَقَالَ رَجُلٌ يَا أَبَا الْقَاسِمِ‏.‏ فَالْتَفَتَ إِلَيْهِ النَّبِيُّ صلى الله عليه وسلم فَقَالَ إِنَّمَا دَعَوْتُ هَذَا‏.‏ فَقَالَ النَّبِيُّ صلى الله عليه وسلم ‏ "‏ سَمُّوا بِاسْمِي، وَلاَ تَكَنَّوْا بِكُنْيَتِي ‏"‏‏.‏
Reference : Sahih al-Bukhari 2120
In-book reference : Book 34, Hadith 73
USC-MSA web (English) reference : Vol. 3, Book 34, Hadith 331
  (deprecated numbering scheme)