People must hold off questioning long enough to fully understand things. Otherwise they could learn nothing. In a class in school, you cannot doubt everything the prof teaches you or you will learn nothing.
Can you tell this to the various creationists who come diving in here while knowing nothing at all about evolutionary biology, cosmology, physics, geology, simple logic (and even spelling and grammer).
You can mention it now and then to the Dawkinists who think that disproving the flood or young earth disproves God too.