First Corinthians, chapter 2, KJVdaily.com

1. And I, brethren, when I came to you, came not with excellency of speech or of wisdom, declaring unto you the testimony of God.
2. For I determined not to know any thing among you, save Jesus Christ, and him crucified.
3. And I was with you in weakness, and in fear, and in much trembling.
4. And my speech and my preaching was not with enticing words of man's wisdom, but in demonstration of the Spirit and of power:
5. That your faith should not stand in the wisdom of men, but in the power of God.

Wisdom

6. Howbeit we speak wisdom among them that are perfect: yet not the wisdom of this world, nor of the princes of this world, that come to nought:
7. But we speak the wisdom of God in a mystery, even the hidden wisdom, which God ordained before the world unto our glory:
8. Which none of the princes of this world knew: for had they known it, they would not have crucified the Lord of glory.

John 1:1-5
1 In the beginning was the Word, and the Word was with God, and the Word was God.
2 The same was in the beginning with God.
3 All things were made by him; and without him was not any thing made that was made.
4 In him was life; and the life was the light of men.
5 And the light shineth in darkness; and the darkness comprehended it not.

9. But as it is written, Eye hath not seen, nor ear heard, neither have entered into the heart of man, the things which God hath prepared for them that love him.

Isaiah 64:4
For since the beginning of the world men have not heard, nor perceived by the ear, neither hath the eye seen, O God, beside thee, what he hath prepared for him that waiteth for him.

10. But God hath revealed them unto us by his Spirit: for the Spirit searcheth all things, yea, the deep things of God.

Jeremiah 17:10
I the Lord search the heart, I try the reins, even to give every man according to his ways, and according to the fruit of his doings.

Spiritual vs. natural

11. For what man knoweth the things of a man, save the spirit of man which is in him? even so the things of God knoweth no man, but the Spirit of God.
12. Now we have received, not the spirit of the world, but the spirit which is of God; that we might know the things that are freely given to us of God.
13. Which things also we speak, not in the words which man's wisdom teacheth, but which the Holy Ghost teacheth; comparing spiritual things with spiritual.
14. 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.

John 3:5-6
5 Jesus answered, Verily, verily, I say unto thee, Except a man be born of water and of the Spirit, he cannot enter into the kingdom of God.
6 That which is born of the flesh is flesh; and that which is born of the Spirit is spirit.

15. But he that is spiritual judgeth all things, yet he himself is judged of no man.
16. For who hath known the mind of the Lord, that he may instruct him? But we have the mind of Christ.

Isaiah 40:13-14
13 Who hath directed the Spirit of the Lord, or being his counsellor hath taught him?
14 With whom took he counsel, and who instructed him, and taught him in the path of judgment, and taught him knowledge, and shewed to him the way of understanding?

First Corinthians 1

First Corinthians 3