A question would NORMALLY be worded “So DO you want someone who belongs to a church but doesn’t ‘really’ believe in it?” Your statement omits the ‘DO’, making it a declaration and not a question in spite of the ‘?’ at the end.
As another example, if I said "you are a liar" that would be reading your mind - that you intended to deceive. But if I said, "that statement is false" it is not reading your mind - it is academic.
The following is not mind reading either:
Likewise, in the above example (the second one) - I might have merely said "False!" - the "That statement is ..." should be understood in normal reading.