Al-Adab Al-Mufrad, Book 34, Hadith 841 (English) ⓘ

Sa'id ibn al-Musayyab reported that his grandfather went to the Prophet, may Allah bless him and grant him peace. He asked, "What is your name?" "Hazn (rough)," he replied. The Prophet said, "You are Sahl (easy)." He said, "I will not change a name which my father gave me." Ibn al-Musayyab said, "Roughness (hazuna) remained among us afterwards."

حَدَّثَنَا عَلِيٌّ، قَالَ‏:‏ حَدَّثَنَا عَبْدُ الرَّزَّاقِ، قَالَ‏:‏ أَخْبَرَنَا مَعْمَرٌ، عَنِ الزُّهْرِيِّ، عَنْ سَعِيدِ بْنِ الْمُسَيِّبِ، عَنْ أَبِيهِ، عَنْ جَدِّهِ، أَنَّهُ أَتَى النَّبِيَّ صلى الله عليه وسلم فَقَالَ‏:‏ مَا اسْمُكَ‏؟‏ قَالَ‏:‏ حَزْنٌ، قَالَ‏:‏ أَنْتَ سَهْلٌ، قَالَ‏:‏ لاَ أُغَيِّرُ اسْمًا سَمَّانِيهِ أَبِي‏.‏ قَالَ ابْنُ الْمُسَيِّبِ‏:‏ فَمَا زَالَتِ الْحُزُونَةُ فِينَا بَعْدُ‏.‏