Muwatta Malik, Book 47, Hadith 8 (USC-MSA) ⓘ
Yahya related to me from Malik that he had heard that the Messenger of Allah, may Allah bless him and grant him peace, said, "I was sent to perfect good character."
وَحَدَّثَنِي عَنْ مَالِكٍ، أَنَّهُ قَدْ بَلَغَهُ أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " بُعِثْتُ لأُتَمِّمَ حُسْنَ الأَخْلاَقِ " .
also referenced under: Book 47, Hadith 1643 (In-Book)