Proverbs 25:26

A righteous man falling down before the wicked is as a troubled fountain, and a corrupt spring.

When a righteous man gives way before the wicked, his witness is spoiled like a fountain made troubled and muddy and like a spring made corrupt and foul. Such falling down does not merely weaken him for the moment but pollutes the very source from which truth should flow clear to others. The righteous must therefore guard speech with care and avoid all error in what is affirmed. The wicked are quick to catch any flaw, to press it, and to demand a retraction, and every such triumph gives delight to Satan.