Now we have received, not the spirit of the world, but the Spirit who is from God, that we might know the things that have been freely given to us by God.
—I Corinthians 2:12
As the apostle Paul begins his first letter to the Corinthians, knowing that he is writing to a congregation divided among various factions, he patiently explains to them what makes them different from those in the world yet at the same time unites the members of the church. He, of course, refers to God's Holy Spirit, given to all Christians at conversion by the laying on of hands. The apostle John calls it "the anointing which you have received from Him" (I John 2:27), implying that Christians have been ordained, and thus set apart or sanctified, to a task or office that others have not been given.
This sets up a dichotomy. On the one side are Christians who have freely received God's Spirit, and on the other are all other human beings who, Paul says, have received "the spirit of the world" (see also Ephesians 2:2). Thus, there is a clash of spirits, a collision of motivating forces, at work between the Christian and the world. The apostle writes in Galatians 5 that the two spirits are diametrically opposed, one producing "the works of the flesh," while the other bears "the fruit of the Spirit" (verses 16-25). In fact, he declares in Romans 8:7, "The carnal mind is enmity against God"; the worldly person, imbibing of the spirit of this world, lives in hostility to God and cannot do what God commands.
The Spirit from God, though, removes the human hostility and allows the Christian to know—that is, realize, understand, and use—the gracious gifts of God. These gifts are predominantly spiritual blessings rather than physical ones. Jesus advises His disciples not to worry about food, drink, and clothing because God knows that physical human beings need such things to live (Matthew 6:25-32). Instead, He says, "Seek first the kingdom of God and His righteousness, and all these things shall be added to you" (verse 33). The Christian's mind is to be focused on God's goal and godly things that will propel him along the way there, and he can do this only by the many gifts bestowed through God's Spirit.
Paul's focus in this passage seems to be on knowledge, understanding, and wisdom. Earlier, he had mentioned that God has chosen to spread the gospel message through preaching, which the worldly Greeks considered "foolishness" (I Corinthians 1:23). Yet, this only exposes the fact that the Greeks did not have the ability to understand spiritual matters, and God would ultimately confound them in their "wisdom" through weak and foolish people preaching a "foolish" message of a crucified Savior. The difference is that those weak and foolish people possess a Spirit that comes directly from the Creator God that allows them to know the truth in all its divine splendor.
Thus, in terms of the apostle's overall goal in persuading the Corinthians that they should "be perfectly joined together in the same mind and in the same judgment" (I Corinthians 1:10), he emphasizes that they have this one commonality, God's Holy Spirit, that makes all the difference to them as individuals and as a congregation. So, as he goes on to say, there is no reason for them to be so judgmental one against the other, for they all "have the mind of Christ" (I Corinthians 2:16). Having one mind and being all in one Body of Christ, as he later discusses (I Corinthians 12:12-27), dividing themselves into cliques is both counterproductive and contrary to God's purpose.