About the year 600BC the Cretan philosopher Epimenides of Knossos said "All Cretans are liars" and thus stated one of the oldest and best known self-referntial paradoxes.
If the statement is true, the nall Cretans ARE liars, but Epimenides himself was Cretan so he must have been lying when he said it. But if he was lying then ... and so on.
Now, I never knew that this paradox is quoted in the Bible. At least I did know because I have read the verse as part of the Letter to Titus but didn't know what it referred to. Reading the book "Aha! Gotcha: Paradoxes to Puzzle and Delight" by Martin Gardner taught me lots, but then I still didn't realise the reference in Titus. (Can't find that book, I must have lent it to someone)
The author of the letter (it is disputed as to whether or not it is Paul) says in Titus 1:12-13 - "Even one of their own prophets has said, "Cretans are always liars, evil brutes, lazy gluttons." This testimony is true."
Bloody typical. Not only does the author miss the point completely, taking it to be an actual observation about Cretans and not as an exercise in logic, he further misquotes and attributes evil, laziness and gluttony to them. see my edit below.
And then to cap it off, in perfect irony, he adds "This testimony is true"
But, if it's true, then the guy who said it ('one of their own prophets') must be a liar so it's not true etc etc.
The author of the letter to Titus shows exactly the same mentality and ignorance that we see in today's popular christian apologists. If you spend any time reading Ray Comfort's blog you'll see what I mean.
I recommend you reach Ray Comfort's blog via the clever and sexy Raytractors. That way you can be vaccinated against the stupid before you inflict it on yourself.
edited to acknowledge my own ignorance, after further research:
The author of Titus is not misquoting, he is working from a stanza in the poem Cretica by Epimenides:
They fashioned a tomb for thee, O holy and high one—
The Cretans, always liars, evil beasts, idle bellies!
But thou art not dead: thou livest and abidest forever,
For in thee we live and move and have our being.
Minos is talking to Zeus, so the Cretan "lie" is that Zeus is dead. Which is yet further irony given that the Cretans seem to have been early atheists, or at least aZeusists.
This poem by Epimenides is also quoted in Acts 17:28