Regeneration is a sovereign work of God (Jn. 1:12-13; 3:3-8; Jas. 1:18; 1 Pet. 1:3) a radical work or total transformation (Ezek. 36:26-27; 2 Cor 5:17); 1 Jn. 3:9) not just an addition…

The SOURCE of regeneration is Christ (1 Pet 1:3; Eph 1:3, 2:4, 4:24; 2 Cor 5:17); the AGENT of regeneration is the Holy Spirit (Jn. 3:3-8; Titus 3:5), the INSTRUMENT of regeneration is the Word of God (Jas. 1:18;  1 Pet. 1:23, 25) which precedes and causes faith.
(Jn 6:63-65; Eph. 2:5; 1 Jn 5:1)

HT: Monergism.com

See also:

MAN-CENTERED GOSPEL VS. GOD-CENTERED GOSPEL