Treatise of Rights · Hadith 4 (#Ḥadīth #3)

وَأَمَّا حَقُّ اللّسَان فَإكْرَامُهُ عَنِ الْخَنَى وتَعْوِيدُهُ الْخَيْرِ وَ تَرك الْفُضُول الَّتي لا فائِدَةِ لَها و البِرُّ بالنَّاسِ و حُسْن القَولِ فيهم.

The right of the tongue is that you consider it too noble for obscenity, accustom it to good, refrain from any meddling in which there is nothing to be gained, express kindness to the people, and speak well concerning them.

Gradings are classical jarḥ-wa-taʿdīl, name-matched to a rijāl index (not individually re-verified).