1 Corinthians 2:14-16, 3:1-3

14 Those who are unspiritual do not receive the gifts of God’s Spirit, for they are foolishness to them, and they are unable to understand them because they are spiritually discerned. 15 Those who are spiritual discern all things, and they are themselves subject to no one else’s scrutiny.

16 “For who has known the mind of the Lord
    so as to instruct him?”

But we have the mind of Christ.

And so, brothers and sisters, I could not speak to you as spiritual people, but rather as people of the flesh, as infants in Christ. I fed you with milk, not solid food, for you were not ready for solid food. Even now you are still not ready, for you are still of the flesh. For as long as there is jealousy and quarreling among you, are you not of the flesh, and behaving according to human inclinations?