When a noble-minded person is able [to take revenge] he forgives, and when he gains possession [of something] he grants generously, and when he is asked [for something] he accords [it]
The noble-minded person forgives despite having the power [to exact revenge], is just in his rule, restrains his harm [from others] and bestows [favours] generously
المصدر : غرر الحكم ودرر الكلم
أَحْسَنُ الْجُودِ عَفْوٌ بَعْدَ مَقْدُرَةٍ
The best generosity is to forgive after gaining the upper hand
Indeed the best of people is one who is forbearing even when he is strong [enough to exact revenge], is not attached to the pleasures of this world even though he is well-off and is just even though he has power
Be forgiving when you are powerful, generous in your affluence and altruistic despite your poverty, then virtue will become perfected for you (or virtues will become perfected for you)