From Jeff Miller:

“Too many inveigh against the evils in society because it take their mind off the evil in themselves. They feel better, as if they had done something: just indignation gives the illusion of justice. So with the reprobation of other’s sins, which happen not to be our own. One can work oneself up to a high state of indignation and return to the enjoyment of one’s own sins with a sense of the good fight well fought”.

Frank Sheed - Christ in Eclipse

Before this he quoted Samuel Butler’s lines about people who:

Compound for sins they are inclined to By damning those they have no mind to.

A reminder to himself he references.