Proverbs 26:23

The Message Bible (MSG)

Smooth talk from an evil heart
is like glaze on cracked pottery.

^24-26Your enemy shakes hands and greets you like an old friend,
    all the while conniving against you.
When he speaks warmly to you, don’t believe him for a minute;
    he’s just waiting for the chance to rip you off.
No matter how cunningly he conceals his malice,
    eventually his evil will be exposed in public.