At-Tirmidhi also related on the authority of Ibn Mas'ud (RAA) that the Messenger of Allah (ﷺ) said:
"The believer is not a slanderer, nor does he curse others, and nor is he immoral or shameless." Related by At-Tirmidhi who graded it to be Hasan. Al-Hakim graded it as Sahih and Ad-Daraqutni said that it is most probably Mawquf (traced only to a Companion).
English reference: Book 16, Hadith 1546
Arabic reference: Book 16, Hadith 1503