Born Again is Necessary for Salvation
The Westminster Confession calls to a necessary element of salvation: "the inward work of the Holy Spirit" (WCF 1:5). John said that "unless one is born again he cannot see the kingdom of God" (John 3:3). Peter said, "Blessed be the God and Father of our Lord Jesus Christ! According to his great mercy, he has caused us to be born again to a living hope through the resurrection of Jesus Christ from the dead" (1 Peter 1:3).
Later in the same chapter Peter further clarifies, "Having purified your souls by your obedience to the truth for a sincere brotherly love, love one another earnestly from a pure heart, since you have been born again, not of perishable seed but of imperishable, through the living and abiding word of God; for 'All flesh is like grass and all its glory like the flower of grass. The grass withers, and the flower falls, but the word of the Lord remains forever.' And this word is the good news that was preached to you" (1 Peter 1:23-25).
Peter tells us that being born again in Christ is a necessary part -- even the foundation -- of the gospel or good news of Jesus Christ. Regeneration is not optional. It is a fact. All Christians are born again, and if someone is not born again s/he is not a Christian. God has sent His Holy Spirit through the ministry of Jesus Christ -- his birth, death and atonement for sin. And there is no salvation apart from the invasion of the Holy Spirit into the life of the believer. Just as God invaded human history through the birth of Jesus Christ, so the Holy Spirit invades our personal lives through the regeneration of individual believers.
The sending of the Holy Spirit is the initial or essential gift of God's grace, for the Holy Spirit carries the message of salvation and redemption to God's people. The Holy Spirit brings the message of salvation to each person individually. Through the Holy Spirit the message of salvation is internalized -- made real in a personal way -- because the Holy Spirit resides within the hearts and minds of Christians.
Paul wants to "impart this in words not taught by human wisdom but taught by the Spirit" (1 Corinthians 3:13). Most versions of the Bible use the word speak rather than impart. The Greek literally means to utter speech. It is important to note that the gospel is shared through words transferred from one person to another, sometimes spoken, sometimes written. This impartation of the Holy Spirit is not magical, but is a function of ordinary speaking and writing. No candles in a darkened room, no special charismatic languages, no mumbo jumbo, no special touch from the master. Just words. Paul's letters provide the example of how it happens.
Paul was converted (born again) on the road to Damascus. He was taught about Jesus Christ by the Spirit, not by men (Galatians 1:1). Paul's conversion changed his heart and mind, and he spent the rest of his life talking about Jesus. His talk consisted of preaching, writing letters and individual counseling or conversations.
Paul tells us that his recommended method of teaching is to compare spiritual things to spiritual things. In other words, worldly things are inadequate to explain spiritual things. Another way to say it is that the truth of Scripture is self-evident to the born again. Or Scripture teaches Scripture. Or analogous things in the world always fall short of biblical truth. The illustration of biblical truths with nonbiblical, worldly stories always falls short.
Would you go to a natural man to learn spiritual truth? Of course not. Would you go to a non-Christian to learn about Christianity? Of course not. And why not? As Paul said, "the natural man does not receive the things of the Spirit of God, for they are foolishness to him; neither can he know them, because they are spiritually discerned" (1 Corinthians 3:14). Show me someone who thinks that Christianity is foolish, and I'll show you a worldly person. The reason that they think Christianity is foolish is that they cannot perceive the reality of God.