The Quran 41:34 (Surah Fussilat)

فارسی
و (هرگز) نیکی و بدی یکسان نیست، همیشه به نیکوترین شیوه پاسخ ده، پس ناگاه (می بینی) همان کس که میان تو و او دشمنی است، گویی دوست صمیمی است.
English
And not equal are the good deed and the bad. Repel [evil] by that [deed] which is better; and thereupon the one whom between you and him is enmity [will become] as though he was a devoted friend.