Al-Adab Al-Mufrad, Book 34, Hadith 815 (English) ⓘ

Jabir said, "A man had a child and named him al-Qasim. We said, 'We will not give you the kunya Abu'l-Qasim nor will we so honour you. The Prophet, may Allah bless him and grant him peace, was told and said, 'Call your son 'Abdu'r-Rahman.'"

حَدَّثَنَا صَدَقَةُ، قَالَ‏:‏ حَدَّثَنَا ابْنُ عُيَيْنَةَ، قَالَ‏:‏ حَدَّثَنَا ابْنُ الْمُنْكَدِرِ، عَنْ جَابِرٍ قَالَ‏:‏ وُلِدَ لِرَجُلٍ مِنَّا غُلاَمٌ فَسَمَّاهُ‏:‏ الْقَاسِمَ، فَقُلْنَا‏:‏ لاَ نُكَنِّيكَ أَبَا الْقَاسِمِ وَلاَ كَرَامَةَ، فَأُخْبِرَ النَّبِيُّ صلى الله عليه وسلم فَقَالَ‏:‏ سَمِّ ابْنَكَ عَبْدَ الرَّحْمَنِ‏.‏