That's irrelevant, bb. It's the statement "without doubt (my deity) exists" that is questionable. If you told ancient Greeks that their God will be replaced, they would have probably chased you from their forum (the real one, not virtual!). Two thousand years from now, some believers may say the same thing about Christ that you said about Zeus "I don't thin many people say that nowadays...our God didn't exits then."
To us, a Christiain God is all we know, just as the Egyptians knew only their gods for just as long, and probably would told you their gods are eternal. But that's a false sense of reality. My older daughter is often amazed when we talk about the 60's and 70's. That's the kind of reality she can't relate to. Think 2,000 years from today.
Again, I will not, because I cannot, "prove that God exists." To subject Him to a "proof" is to misunderstand Who He Is a priori. Such a proof would then be worthless.
Proving that God exists wold not be worthless, bb! It would be the greatest discovery known to mankind.
Even Thomas doubted.