The best lie is the worst.

A lie may be called “best” because it is convincing, but that quality can make it especially harmful. The easier a falsehood is to believe, the more readily it can mislead someone.

The proverb turns praise into criticism: skill does not make deception admirable. It suggests that a particularly persuasive lie deserves greater concern, not greater respect.

Use this proverb when someone admires a clever deception or overlooks the harm it could cause. It can also serve as a warning that a believable claim deserves scrutiny when there is reason to suspect it is false.