1 Corinthians 2:11

2:11 For who among men knows the things of a man except the man’s spirit within him? So too, no one knows the things of God except the Spirit of God.

1 Corinthians 2:14-15

2:14 The unbeliever does not receive the things of the Spirit of God, for they are foolishness to him. And he cannot understand them, because they are spiritually discerned. 2:15 The one who is spiritual discerns all things, yet he himself is understood by no one.