Wisdom in speech versus foolish impulsivity
Nahj al-Balāgha|Volume 1|Book 3|Chapter 40
٤٠. وَقَالَ (عليه السلام) : لِسَانُ الْعَاقِلِ وَرَاءَ قَلْبِهِ، وَقَلْبُ الْأَحْمَقِ وَرَاءَ لِسَانِهِ.
40. Amīr al-mu’minīn, peace be upon him, said: The tongue of the wise man is behind his heart, and the heart of the fool is behind his tongue.