لا تَغتَبْ فتُغتَبُ، ولا تَحفِرْ لِأخِيكَ حُفرَةً فَتَقَعَ فيها؛ فإنَّكَ كما تَدينُ تُدانُ.
Do not backbite lest you become a victim of backbiting, and do not dig a hole for your brother lest you fall in it yourself, for you will be paid back whatever you put in.
Bihar al-Anwar, v. 75, p. 249, no. 16