“My brother ought not to have treated me thus.”
True: but he must see to that. However he may treat me, I must deal rightly by him. This is what lies with me, what none can hinder.
Your expression of virtue need not be conditional. It can and must be absolute. Your thoughts, words and deeds should be actively forged upon the anvil of truth, rather than passively formed in reaction to outer circumstance. No man, no matter how egregious his offense, can hinder you from taking up this sacred hammer.