Although the term is not used equally by all Christian traditions, many if not most basic aspects of Christian theology require a supernatural explanation.
To name but a few key examples, these include the nature of the Trinity, the Virgin Birth of Jesus, and the Resurrection of Jesus.
These are mysteries in the sense that they cannot be explained or apprehended by reason alone.
The virgin birth!
The virgin birth of Jesus is the belief that Jesus was conceived in the womb of his mother Mary through the Holy Spirit without the agency of a human father and born while Mary was yet a virgin. How is this possible?
The New Testament references are Matthew 1:18-25 and Luke 1:26-38. It is believed to follow the prophetic message in Isaiah 7:14. It is not expressly mentioned elsewhere in the Christian scriptures, and “the modern scholarly consensus is that the doctrine of the virgin birth rests on a very slim historical foundation.”
However, Psilanthropists argue against the virgin birth and contend that Jesus was a “mere human”.
Was it a supernatural phenomena?