The destructive power of unrestrained speech
Nahj al-Balāgha|Volume 1|Book 3|Chapter 60
٦٠. وَقَالَ (عليه السلام): الِّلسَانُ سَبُعٌ، إِنْ خُلِّيَ عَنْهُ عَقَرَ.
60. Amīr al-mu’minīn, peace be upon him, said: The tongue is a beast; if it is let loose, it devours.