La darar wa la dirar
لَا ضَرَرَ وَلَا ضِرَارَ
La darara wa la dirar.
"There should be no harming and no reciprocating harm."
Narrated by Abu Sa'id al-Khudri. Sunan Ibn Majah 2341 (hasan) · Nawawi's Forty · #32
A short reflection
Two verbs, and the whole body of Islamic civil law stands on them. Don't harm. And don't match harm with harm.