Fool's heart in mouth, wise man's tongue in heart

Nahj al-Balāgha|Volume 1|Book 3|Chapter 41

Nahj al-Balāgha

Book 3, Chapter 41

Fool's heart in mouth, wise man's tongue in heart

Hadith #54

ومعناهما واحد.

The meaning of both the sayings (40 and 41) is the same.