There is a chiastic structure in 1 Cor 3 which spans back to the beginning of the letter:
1a) 1 Cor 1:4-9, The grace of God which was given to you in Christ Jesus, so that you come short in no gift;
1b) 1 Cor 1:10-17, Divisions in the church: I am of Paul, Apollos, Cephas, or Christ;
1c) 1 Cor 1:18-25, The cross is foolishness to those who are perishing;
1d) 1 Cor 1:26-31, That no flesh should glory in His presence;
1e) 1 Cor 2:1-5, Paul’s initial preaching + he knew not anything among them but Jesus Christ and Him crucified;
1f) 1 Cor 2:6-8, We speak the wisdom of God in a mystery among those who are mature;
1g) 1 Cor 2:9, Eye has not seen nor ear heard the things which God has prepared for those who love Him;
1h) 1 Cor 2:10, But God has revealed them to us through His Spirit;
central axis) 1 Cor 2:10b-11, “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;”
2h) 1 Cor 2:12a, We have received the Spirit who is from God;
2g) 1 Cor 2:12b, That we might know the things freely given to us by God;
2f) 1 Cor 2:13-3:4, These things we speak to the spiritual vs. the natural (carnal or immature) man;
2e) 1 Cor 3:5-15, Ministers who built the church from the foundation of Jesus Christ;
2d) 1 Cor 3:16-18a, Let no one deceive himself;
2c) 1 Cor 3:18b-20, The wisdom of this world is foolishness with God;
2b) 1 Cor 3:21a, Therefore let no one boast in men;
2a) 1 Cor 3:21b-23, For all things are yours, and you are Christ’s, and Christ is God’s.
There is a wisdom of the world, in our cultures, which we in the assembly of the believers come out of. It permeates our world. That wisdom, which is natural and carnal, is opposed to the Spirit of God. Furthermore, those “wise men” of the world who claim to teach the world about God without His Spirit, do not know anything of Him, because it is only by His Spirit that the things of God can be known.
Let us not forget, that the Spirit and the Word always agree. The Word was spoken from the heart or Spirit of the LORD (out of the abundance of the heart, the mouth speaks). When we hear something that sounds good, we must ALWAYS check it against the Word of God, and if it does not agree, then it is not of the Spirit of God. No matter how good a “wise man” makes it sound, it is devoid of the things of God.