think you should at least admit, that at the current point, as the field stands, that it is reasonable to believe that the universe began to exist. Physicists have no trouble with the idea of eternal-future, and it would not surprise me if eternal-past became evidenced at some point either. The trouble is that, as every good philosopher should know, that the two eternals you speak of are of a different order. The eternal-future is merely potential. The past-eternal has to be actual. Which is impossible (see the philosophical proofs for the beginning of the universe). But on this topic, and about the confirmation bias. I do think that if the evidence arose that the universe might be eternal-past that some christians would start to use the whole genesis-'bara' thing as evidence that the bible is right again! It is in exactly this way that I think that the confirmation bias is at play with religion. People base their arguments and evidence and epistemologies upon what they want to believe. This explains so much about religions. Not Christianity. For approximately 1900 years Christianity affirmed that the universe began to exist, and this against the tide of popular opinion. It was long considered more reasonable to believe that the universe was eternal. In effect, the problems you are having with the concept of the universe having an beginning are the same problems that have always troubled unbelievers about the Judeo-Christian tradition. (It has always been staunch in this area, and it