How can Christians look at Zeus and determine it's a fake god and yet believe the Christian god is real?

I just don't get it. There is no more evidence for Zeus than there is for the Christian god. Zeus is an older god than the Christian god. Books mentioning Zeus like the Iliad are older than the New Testament. A lot of Christian dogma is actually based on old Greek religions. So all the truth verification standards Christians apply to their religion can be applied to Zeus and Zeus actually comes up as more plausible than the Christian god. Yet the Christians casually dismiss Zeus, claim Zeus is not real and then go on believing an even faker god than Zeus. What mental defect cause such a warped mental process?