1 Corinthians 2:14

14 The person without the Spirit does not accept the things that come from the Spirit of God but considers them foolishness, and cannot understand them because they are discerned only through the Spirit.

Read 1 Corinthians 2:14 Using Other Translations

But the natural man receiveth not the things of the Spirit of God: for they are foolishness unto him: neither can he know them, because they are spiritually discerned.
The natural person does not accept the things of the Spirit of God, for they are folly to him, and he is not able to understand them because they are spiritually discerned.
But people who aren’t spiritual can’t receive these truths from God’s Spirit. It all sounds foolish to them and they can’t understand it, for only those who are spiritual can understand what the Spirit means.