Proving God Existence

[pocaracas]

The universe post big bang is finitely old, but as we know nothing about the pre-big bang universe, it may or may not have infinite age. But it is still a faulty assumption.

Yes, this is true. But now we're getting into 'weird' technical details.
For the purpose of the OP, I'm assuming he's talking about 'time as we know it within our universe'.
Even if there's time 'outside' or 'before' the big bang (which they may not even be), it's not 'our time', and may not function in a linear fashion like the time we know.
Which I guess again, would knock out the "time is infinite" assumption.

Oh, if you want to go all sci-fi about it, youcan even speculate that time 'outside' our universe may even be multi-dimensional. Maths allows for it, but my mind can't begin to fathom what that may be like!