I Corinthians 2:10-11, 16

But God has revealed them to us through His Spirit. For the Spirit searches all things, yes, the deep things of God. For what man knows the things of a man except the spirit of the man which is in him? Even so no one knows the things of God except the Spirit of God.

For “who has known the mind of the LORD that he may instruct Him?” But we have the mind of Christ.