Fred Clark at Slacktivist comments on a series of "Church Sign Epic Fails," including an apparently large number trafficing in sexual innuendo:
That last category is a big one. Jesus told his disciples to be wise as serpents and innocent as doves. Some of the folks in charge of these signs, God bless ‘em, have got the innocent as doves part down. What they need is some kind-hearted, filthy-minded neighbor who’d be willing to supply a bit of serpently wisdom — somebody who can look over the copy for next week’s sign before it goes public.
They need someone who could warn them ahead of time that “Behold, I come quickly” is likely to inspire too many giggles from passersby, never mind why. Or who could gently inform the Christian Outreach Church to reword the name of their C.O.C. Block Party. Or who could say, “Psalm 16:11 is a lovely verse, but you don’t want to put ‘In your right hand are pleasures for evermore’ on your sign.”
Fred goes on to offer additional advice on some phrases to avoid. And really, you don't need to be very pervy at all to figure this stuff out.