'Mystery' in the Bible

He asked them to pray for mercy from the God of heaven concerning this mystery so that he and his friends would not be destroyed along with the rest of the wise men of Babylon.

Then in a night vision the mystery was revealed to Daniel. So Daniel praised the God of heaven,

Daniel replied to the king, "The mystery that the king is asking about is such that no wise men, astrologers, magicians, or diviners can possibly disclose it to the king.

As for me, this mystery was revealed to me not because I possess more wisdom than any other living person, but so that the king may understand the interpretation and comprehend the thoughts of your mind.

The king replied to Daniel, "Certainly your God is a God of gods and Lord of kings and revealer of mysteries, for you were able to reveal this mystery!"

saying, "Belteshazzar, chief of the magicians, in whom I know there to be a spirit of the holy gods and whom no mystery baffles, consider my dream that I saw and set forth its interpretation!