«زَيِّ الْعَقْرَبَهْ يُقْرُصْ وِيِلْبَدْ»

The image is a scorpion that delivers its sting and then flattens itself out of sight, motionless, so no one can say where the pain came from. Some tellings use a snake instead, with the same sense of hidden harm.

Applied to people, it marks someone who does damage covertly and then keeps a low profile, so suspicion never settles on them; the masculine verbs point to the person described, not the scorpion. It warns that a calm, quiet person may be the hidden source of trouble.

Use it about someone suspected of causing harm while avoiding blame, such as a colleague who sabotages quietly or a relative who stirs trouble behind the scenes. It is an accusation, so saying it about someone present can insult; it suits complaints and warnings among people who share the suspicion.