Regeneration. a word used to describe the radical and permanent change in a person's whole outlook achieved by the Holy Spirit. The word itself is used only twice in the NT, in Mt. 19:28 ('new world', RSV) to refer to the future restoration of everything and in Tit. 3:5 to refer to the change in an individual. Other terms, which relate to it are 'new birth' (Jn. 3:3; 7:1, Pet 1:3,23), describing the continuous application and expression of regeneration. It was prefigured in the OT by such passages as Je. 31:31ff., which sees God's law written on human hearts and Ezk. 37:1ff., Ezekiel's vision of dry bones brought to life by God's breath.
The NT regards the effects of sin to be so serious that without regeneration a person cannot enter the kingdom of God. The initiative is God's, whose decisive act of regenerating someone is once and for all (Jn. 1:13, 3:3ff.) As a result, the individual actively repents, believes in Jesus, and then lives in newness of life (cf. 1 Jn 3:9, 4:7; 5:1). There is no change to the personality itself, but the person is controlled differently; instead of being ruled by the law of sin, he or she is directed by the Holy Spirit towards God. However, the regenerate person is not yet perfect, but has to grow (1 Pet 2:2) and be continually filled with the Spirit (Rom 8:4, 9, 14; Eph 5:18).
The means by which regeneration is ministered to a person have been disputed. 1 Pet 1:23 and Jas. 1:18 refer to God's Word as a means of new birth, Tit 3:5 relates it to baptism. But as John distinguishes between regeneration and the faith that results (Jn. 1:12f.), Peter and James are referring to the whole process, not the means. Also regeneration is possible before baptism (Acts 10:33f.; 16:14f.). Therefore regeneration comes to people directly from the Holy Spirit; God's word brings it to expression in faith and repentance; and baptism bears witness to it.
The New Concise Bible Dictionary (IVP), pg 470
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