Surah An-Nahl Verse 126 - English Translation by Shabbir Ahmed
Surah An-Nahlوَإِنۡ عَاقَبۡتُمۡ فَعَاقِبُواْ بِمِثۡلِ مَا عُوقِبۡتُم بِهِۦۖ وَلَئِن صَبَرۡتُمۡ لَهُوَ خَيۡرٞ لِّلصَّـٰبِرِينَ
Hence, if you have to respond to an attack in argument, respond only to the extent of the attack leveled against you. But to bear with patience is indeed far better for the steadfast