There never was an angry man who thought his anger unjust.
Attr. to St. Francis de Sales, who did say it, sort of. I looked at this years ago (pre-blogging days), and here’s what I found:
St. Francis de Sales said this in Introduction to the Devout Life, but he didn’t originate the quotation. He is explicitly quoting St. Augustine’s “Letter to Profuturus” (Letter 38). Here’s what St. Augustine wrote:
And well do you know, my excellent brother, how, in the midst of such offenses, we must watch lest hatred of any one gain a hold upon the heart, and so not only hinder us from praying to God with the door of our chamber closed, but also shut the door against God Himself; for hatred of another insidiously creeps upon us, while no one who is angry considers his anger to be unjust. For anger habitually cherished against any one becomes hatred, since the sweetness which is mingled with what appears to be righteous anger makes us detain it longer than we ought in the vessel, until the whole is soured, and the vessel itself is spoiled. Wherefore it is much better for us to forbear from anger, even when one has given us just occasion for it, than, beginning with what seems just anger against any one, to fall, through this occult tendency of passion, into hating him.
Good advice, I think.
Anyhow, this is a rare example of a quote’s being taken away from St. Augustine (who is often on the receiving end of fauxtating) and being assigned to someone else. Granted, many translations of the Introduction don’t put this passage in quotation marks, so it would be easy enough to conclude that it is St. Francis’s commentary on what St. Augustine said.