REWARDING AN EVIL WITH ANOTHER
Question:
Somebody at work spread false rumors against a colleague, an ignoble deed that caused the former some harm and anguish. The slandered and disgruntled man returned the favor to his attacker by doing exactly the same to him. What is the ruling in This?
Answer:
Each one of them has wronged the other, and each one of them should ask the other to absolve him for the wrong. If that doesn't happen, then it is Allah Almighty who will judge between His servants on the Day of Judgement. Both of them should also sincerely repent to Allah Almighty.
Permanent Committee for Research and Verdicts
Fatawa Islamiyah Darussalam Vol : 8 page no. 105