Virtues and Merits of the Prophet (pbuh) and his Companions

Bukhari :: Book 4 :: Volume 56 :: Hadith 759

Narrated 'Abdullah bin 'Amr:

The Prophet never used bad language neither a "Fahish nor a Mutafahish. He used to say "The best amongst you are those who have the best manners and character." (See Hadith No. 56 (B) Vol. 8)