The Book Pertaining to Repentance and Exhortation to Repentance (Kitab Al-Tauba)
Muslim :: Book 37 : Hadith 6621
Abu Ayyub Ansari reported that Allah's Messenger (may peace be upon him) said: If you were not to commit sins, Allah would have swept you out of existence and would have replaced you by another people who have committed sin, and then asked forgiveness from Allah, and He would have granted them pardon.