A Higher Plane of Existence:
We should not be suprised that Higher Plane of Existence is real. (aka heaven). This universe is such a miracle that it exists, with it’s laws purpose to create and support life, that it would near impossible for THIS universe to exist. If our existence is possible, then it is surely also possible that a higher plane can exist. I don’t claim that in interacts with ours in some way, that’s pure speculation. But I can see that it’s just as likely to exist as our normal reality.
The New Testament extended and replaced much of the Old Testament. Our new Beliefs are valid in doing the same with the whole Bible. We no longer need supernatural beliefs, but we need spiritual Ones. If it were valid, and NEEDED, for the New Testament to come into being, then we can also say it’s valid and NEEDED for our own modern Testament.