I don’t understand. How do we know they were liars?
Titus 1:12
(12) One of themselves, even a prophet of their own, said, The Cretans are always liars, evil beasts, slow bellies.
Ergo the Cretan Paradox:
Epimenides the Cretan says “All Cretans are liars.” This statement, because it was uttered by a Cretan, is true if and only if it is false.