A false witness will not go unpunished, and he who breathes out lies will perish.
Proverbs 19:9 ESV

Almost exactly the same as v5, but the negative side of v5 is passive, while v9 is active: "will not escape" vs "will perish".

Liars will not inherit the Kingdom of Heaven. Even if they escape punishment in this life, they won't escape the final judgment.