Sahih al-Bukhari 3115
Sahih al-Bukhari · Book 57: One-fifth of Booty to the Cause of Allah (Khumus) · The Statement of Allah تعالى: "Verily one-fifth (1/5th) of it is assigned to Allah and to the Messenger ﷺ ..." (V.8:41)
Narrated Jabir bin `Abdullah Al-Ansari:
حَدَّثَنَا مُحَمَّدُ بْنُ يُوسُفَ ، حَدَّثَنَا سُفْيَانُ ، عَنِ الأَعْمَشِ ، عَنْ سَالِمِ بْنِ أَبِي الْجَعْدِ ، عَنْ جَابِرِ بْنِ عَبْدِ اللَّهِ الأَنْصَارِيِّ ، قَالَ وُلِدَ لِرَجُلٍ مِنَّا غُلاَمٌ فَسَمَّاهُ الْقَاسِمَ فَقَالَتِ الأَنْصَارُ لاَ نَكْنِيكَ أَبَا الْقَاسِمِ وَلاَ نُنْعِمُكَ عَيْنًا، فَأَتَى النَّبِيَّ صلى الله عليه وسلم فَقَالَ يَا رَسُولَ اللَّهِ وُلِدَ لِي غُلاَمٌ، فَسَمَّيْتُهُ الْقَاسِمَ فَقَالَتِ الأَنْصَارُ لاَ نَكْنِيكَ أَبَا الْقَاسِمِ وَلاَ نُنْعِمُكَ عَيْنًا. فَقَالَ النَّبِيُّ صلى الله عليه وسلم " أَحْسَنَتِ الأَنْصَارُ ، سَمُّوا بِاسْمِي، وَلاَ تَكَنَّوْا بِكُنْيَتِي، فَإِنَّمَا أَنَا قَاسِمٌ " .
A man amongst us begot a boy whom he named Al-Qasim. On that the Ansar said, (to the man), "We will never call you Abu-al-Qasim and will never please you with this blessed title." So, he went to the Prophet and said, "O Allah's Messenger (ﷺ)! I have begotten a boy whom I named Al-Qasim and the Ansar said, 'We will never call you Abu-al-Qasim, nor will we please you with this title.' " The Prophet (ﷺ) said, "The Ansar have done well. Name by my name, but do not name by my Kunya, for I am Qasim."