Regeneration is the work of the Holy Spirit that brings a sinner from spiritual death into spiritual life. While Christians may disagree about such issues as the relationship between regeneration and baptism, or whether regeneration precedes faith, it is biblically faithful for a follower of Jesus to say, “I am regenerated.”
While the Greek noun palingenesia appears only twice in the New Testament (Matt. 19:28; Titus 3:5), the concept of regeneration, or new birth, is a consistent theme of Jesus and the New Testament writers. Jesus makes it clear that people must be “born again,” or “born of the Spirit,” if they are to see the kingdom of heaven (John 3:3, 5).
The work of the Holy Spirit, making an individual a “new creation” (2 Cor. 5:17; Gal. 6:15), prepares that person for the future work of Christ as He creates “new heavens and a new earth” (2 Pet. 3:13). All those the Spirit regenerates are assured a place with Christ when He refurbishes the cosmos, purging it completely of sin and its stain.
Regeneration is necessary because the Bible describes unbelievers as the walking dead. Not only are they spiritually dead (Eph. 2:1), but they are depicted as natural / without the Spirit (1 Cor. 2:14); blinded in their minds (2 Cor. 4:4); bound by Satan (2 Tim. 2:26); alienated from God (Eph. 4:17-18); enemies of the Lord (Rom. 5:6-11; Col. 1:21-22); condemned in their unbelief (John 3:18); and in spiritual darkness (Acts 26:18; Eph. 5:8; Col. 1:13; 1 Pet. 2:9).
Regeneration is a one-time, non-repeatable act by which the Holy Spirit enters the dead human spirit of a sinner and makes him or her spiritually alive. Regeneration also is permanent. That is, a person whom God foreknows, predestines, calls, justifies, and glorifies cannot lose the gift of regeneration without losing all of the associated links in God’s golden chain of redemption.