I'll be the first to admit that I have no idea. Especially since...well, given what we saw with Xishen and the other faithful in the cave. I'll ask her about it, next chance I get to do that.

Otherwise, I don't know how close they can get; what's important to them is their beliefs. The way they feel about it, whether or not they feel like it calls to them personally... Matters of the spirit are powerful motivators.