Sahih al-Bukhari 3387
In-book no 3387حَدَّثَنَا حَفْصُ بْنُ عُمَرَ، حَدَّثَنَا شُعْبَةُ، عَنْ حُمَيْدٍ، عَنْ أَنَسٍ ـ رضى الله عنه ـ قَالَ كَانَ النَّبِيُّ صلى الله عليه وسلم فِي السُّوقِ فَقَالَ رَجُلٌ يَا أَبَا الْقَاسِمِ. فَالْتَفَتَ النَّبِيُّ صلى الله عليه وسلم فَقَالَ " سَمُّوا بِاسْمِي، وَلاَ تَكْتَنُوا بِكُنْيَتِي ".
Narrated Anas: While the Prophet (ﷺ) was in the market, a man called (somebody), "O Abu-l-Qasim!' The Prophet (ﷺ) turned to him and said "Name yourselves after me but do not call yourselves by my Kuniya."