sverresverre, you are comparing apples and oranges.
1 + 1 = 2 because addition is *defined * such that 1 + 1 = 2. Mathematics is a human construct, that has no external reality whatsoever. It is a thing of symbols only - have you ever held a 1 or a 2 in your hand? No, because there is no such thing as a 1 or a 2. It’s not a matter of taking it on faith that 1 + 1 = 2. It must be so because we have defined addition in that way. What math does is to postulate a certain set of “operations” such as addition, substraction, etc, and a set of rules.
Now, the interesting thing about this totally artificial construct mathematics is how useful it is in describing reality. We have never seen a situation that could be represented by 1 + 1 that did not equal 2. We don’t expect we ever will. So mathematics becomes an excellent predictor of what will happen under many different circumstances. Probably the vast majority of technology you use was developed using mathematics. Why? Because this set of rules and operations that human beings came up with fits our experience so completely. But it is still an artificial construct, and we know this. So we know, based on the millenia of experience we have with it, that correctly applied mathematics is extremely likely to conform to external reality. We call this modelling, and although the term is recent, the concept is very old.
Religion is describing an external reality. There either is a god or there isn’t. There either was a Jesus or there wasn’t. And so on. It is not, nor does it purport to be, an abstract set of symbols that accurately reflect external reality. It is external reality, or at least that is what it claims to be.
External reality lends itself to evidence, to experiential proof. You know the table in front of you is solid (at the macro level) because you can rest your hand on it, and so can any other person who tries (assuming they have a hand). In essence, that what the scientific method is. It postulates something: the table is solid. And then it sets up replicable tests: you rest your hand on the table, and so does the next guy and the next and the next. *Anyone * who attempts to rest his/her hand on the table can do so. And other people can see them doing so. There is evidence.
Mathematics isn’t the same kind of thing. It can’t be seen, felt, heard, or sensed in any way. It’s simply a humanly defined tool, a set of abstract concepts that, thus far, have accurately corresponded to our experience of external reality. There’s no faith about it, except the faith that because it has always done so in the past, it always will correspond to external reality. If, in fact, it fails to do so, then the chances are that the abstract definitions we created and called mathematics are simply wrong, and need to be re-defined.
Religion claims to be external reality. It therefore lends itself to evidence, proof. Mathematics is a symbolic construct. They are not comparable.