"For the Spirit searches all things, yes, the deep things of God" (1 Cor. 2:10).
While anyone can recite the Scriptures, understand complex theological concepts, even see the reasonableness of Christ’s teaching, true Christian knowledge, what Paul calls the wisdom of God, is much more. The natural man (1 Cor. 2:14) does not have the Spirit of God, and even though he might be familiar with Christian ideas, he does not possess a deeper understanding of the Gospel and the ways of God. This is because the spirit of man cannot know the mind of God. As Paul says, just as no one knows the thoughts of a man but the man himself, so no one knows the thoughts of God but God Himself. Therefore, the only person competent to reveal the hidden mysteries of God, the thoughts and purposes of God in redemption, is a divine person—the Spirit of God.
When Paul says that the Holy Spirit searches the things of God, this does not mean that the Spirit is looking for something He does not already know, just as God is not looking for something hidden when He searches the hearts of man. This phrase means that God knows every twist and turn of our thoughts, imaginations, and desires. Likewise, the Spirit of God knows the profound, mysterious thoughts of God, the depths of God, the inmost recesses of His being, perfections, and purposes. The Spirit, therefore, is fully capable to reveal that wisdom that had been for ages hidden in the counsels of God.
The work of the Spirit in revealing the wisdom of God to natural man is called illumination. This does not mean that we are given new revelation, but it is a work within that enables us to understand and accept the revelation of the Bible. The Spirit gives us spiritual understanding, spiritual discernment (Col. 1:9; 1 John 5:20). He unveils our minds and applies God’s revealed truth to our hearts so that we see and embrace the excellency of God, of Christ, of His glorious perfections.
While many people might hear the proclamation of the Gospel, only those who have been enabled by the Spirit, enlightened by His grace, will truly understand the purposes of God and embrace Christ for who He is, not for who they want Him to be. This illuminating work of the Spirit begins at our regeneration and continues throughout our lives as we grow in understanding God and His ways.
Skim through the gospel of John and notice how the apostle uses light in reference to spiritual understanding. Before you study the Scripture, before you make decisions, before you begin to wrestle with a difficult doctrine or teaching, pray that the Spirit would illumine your mind to His truth.