You have certainly ventured into "make believe land" if you think that religiously motivated people are going to line up so that you can tell them what a pack of hypocrites they are. Withes do in fact exist--but i suspect that the word you wanted was witches--this is an example of why it's useful to be careful of what one writes. As for whited sephulchres full of dead men's bones and all things unclean, that's a reference to a passage of scripture, and one which is appropriate to your theme. If you're going to take on a religion, such as christianity, it's helpful not to be completely ignorant of what, in fact, the adherents believe.
Matthew, chapter 23, verses 27 and 28, in the King James version:
Woe unto you, scribes and Pharisees, hypocrites! for ye are like unto whited sepulchres, which indeed appear beautiful outward, but are within full of dead men's bones, and of all uncleanness.
Even so ye also outwardly appear righteous unto men, but within ye are full of hypocrisy and iniquity.