Narrated Jabir bin 'Abdullah: A man among us begot a boy whom he named Al-Qasim. The people said (to him), "We will not call you Abul-lQasim, nor will we please you by calling you so." The man came to the Prophet and mentioned that to him. The Prophet said to him, "Name your son 'Abdur-Rahman."
— Sahih Bukhari, Volume 8, Book 73: Good Manners and Form (Al-Adab), Hadith #208