at least half the people here started their journey into rationalism by ignoring the big bright warning sign saying "Don't question God!"

Your edit is perfectly sufficient and I have no criticisms of it. However, the point can be expanded upon such that it will seem different and it may appear I am disagreeing.

The metaphorical signs that exist invoke the idea "Don't question God!", but in the West, that's not too close what they actually say. In religious communities at least moderately touched by the enlightenment, enough distaste of signs reading "Don't question God!" has been absorbed that such signs would be disrespected as low status.

This is something a member of a moderate strain of fundamentalism might pride himself or herself on, as a factor that distinguishes him or her from literalists, perhaps as an important part of his or her identity.

To make someone think "Don't question God (this time)!", the sign might say something like "You don't know what the consequences would have been had those people lived. God does, so rely on his judgment."

The "this time" will happen to be every time, but the universality of it won't be derived from so general a rule; it will be a contingent truth but not a logical one exactly.