That when his grandfather, Hazn visited the Prophet (ﷺ) the Prophet (ﷺ) said (to him), "What is your name?"
He said, "My name is Hazn." The Prophet (ﷺ) said, " But you are Sahl." He said, "I will not change my
name with which my father named me." Ibn Al-Musaiyab added: So we have had roughness (in
character) ever since.
Sahih al-Bukhari Book 78, Hadith 217