1 Corinthians 2:7-15 NASB
but we speak God’s wisdom in a mystery, the hidden wisdom which God predestined before the ages to our glory; the wisdom which none of the rulers of this age has understood; for if they had understood it they would not have crucified the Lord of glory; but just as it is written,
“THINGS WHICH EYE HAS NOT SEEN AND EAR HAS NOT HEARD,
AND which HAVE NOT ENTERED THE HEART OF MAN,
ALL THAT GOD HAS PREPARED FOR THOSE WHO LOVE HIM.”
For to us God revealed them through the Spirit; for the Spirit searches all things, even the depths of God. For who among men knows the thoughts of a man except the spirit of the man which is in him? Even so the thoughts of God no one knows except the Spirit of God. Now we have received, not the spirit of the world, but the Spirit who is from God, so that we may know the things freely given to us by God, which things we also speak, not in words taught by human wisdom, but in those taught by the Spirit, combining spiritual thoughts with spiritual words.
But a natural man does not accept the things of the Spirit of God, for they are foolishness to him; and he cannot understand them, because they are spiritually appraised. But he who is spiritual appraises all things, yet he himself is appraised by no one.
NASB: New American Standard Bible