Gregory the Great, on Prov 18:17

“The just is first accuser of himself: his friend cometh, and shall search him.”

“Those even who do not believe that they have sinned, generally confess themselves sinners. For it is frequently the case, that men openly confess themselves sinners, but on hearing a true account of their sins, when other persons attack them, they boldly defend themselves, and endeavour to appear innocent. Every one, then, of this character, if he says that he has sinned, speaks untruly; inasmuch as he proclaims himself a sinner not from the inmost heart, but in words only. For since it is written, "The just man in the beginning accuseth himself," he wished to gain credit, not to be humbled, by confessing his sin: he desired, by accusing himself, to appear humble, without being so. For did he really wish to be humble, by confessing his sin, he would not attack others when convicting him of the commission of it. The righteous then, in passing sentence on his own conduct, knows from the bottom of his heart, by the examples of holier men, that he really is what he professes to be.”

Imported from an open dataset — not yet checked against the printed edition.