When we say the concept of GOD is unbelievable. Belief in the Bible is a belief in fairy tales. Or belief in the supernatural is untenable because Science does not support it. We don’t seem to realize that belief in anything in this world is an act of faith.
Atheism, Evolutionism, Naturalism, Nihilism, you name it! Life began suddenly. Life here was a virgin birth. That is both miraculous and supernatural.
We should be fair, we should strive for honesty. If it is believable for alternative worldviews, it has to be true concerning GOD/JESUS & the HOLY SPIRIT.
(Paraphrased: Vince Vitale and a little bit of me 🙂 )