User blog comment:Fedguy/Christianity is real in Arrowverse?/@comment-28051289-20170323231051

The Arrowverse already established that the African trickster god Anansi was real, so I don't see it as "Christianity is true" so much as "all religions are partially true". And if you count Constantine as canon, they already established Judeo-Christian beings like Angels and Demons as real. But Constantine established the gods of Voodoo and other mystical traditions to be real too, so again, it's a mixed bag.

And Legends of Tomorrow didn't even specify that Jesus was God, just that he existed (which is probably true in the real world, according to most historians) and that he was somehow tied to very powerful supernatural forces (which isn't that much of a stretch in a universe where magic is real). Maybe Jesus was just an especially powerful sorcerer in the Arrowverse, I think the writers deliberately left it ambiguous for the very reason you mention.