'Mysteries' in the Bible

One should think about us this way -- as servants of Christ and stewards of the mysteries of God.

And if I have prophecy, and know all mysteries and all knowledge, and if I have all faith so that I can remove mountains, but do not have love, I am nothing.

For the one speaking in a tongue does not speak to people but to God, for no one understands; he is speaking mysteries by the Spirit.