5Jesus answered, Verily, verily, I say unto thee, Except a man be born of water and of the Spirit, he cannot enter into the kingdom of God. (John3:5)
Not the natural birth, for Nicodemus already had this birth and he was told he had to be born again of both water and Spirit.
Not water baptism: (Heb.11; Rom.3:23-25; Heb. 9:15;Rom.4; Gal.4:29; Jas. 2:23; Ps.32:5; 103:3; Lk. 1:70; Acts 3:21; Dt.32:18; 2 Pe.1:21).
They all had the Holy Spirit, gifts, and many blessings without water baptism(Ps.51:12;1kings 3:12; 4:29-34; Num.11:17-29; Acts 3:21; Lk.1:15-17,41,46,67; 2:25-38; Heb.11).
Many in Christ's ministry were forgiven without water baptism(Mt.9:1-7,22; Mk.5:34; 10:52; Lk.7:48; 17:19; 18:9-14; 19:1-9; 23:43; Jn.4:49-53; 7:31; 8:30-31; 11:45; 12:11,42).
Men have been baptized in the Holy Spirit before water baptism(Acts9:17; 10:44-48; 11:14-18; 15:7-11).
Christ was baptized in water without forgiveness of sins( Mt.3:15-17).
It is a mere "figure"(1Pet.3:21)
and a "witness" (1Jn.5:6-10),
but not held as essential for salvation( 1Cor.1:23-24; 15:1-5; Rom.1:16; 10:9-14; Eph. 2:8-9; Acts 10:43; 13:38-39; 16:31; Jn. 3:14-18,36; 5:24; 1Jn.5:1).
It is only for men who have repented( Mt.3:2-6; 28:19; Acts 2:38-41; 8:12, 37; 10:43-48; 18:8; 19:4).
Water is used in a figurative sense of Salvation(Jn.4:14; Isa.12:3), of the Spirit Baptism (Jn.7:37-39),
and of cleansing by the Word of God(Jn.15:3; Eph.5:26).
Since men are cleansed and born again by the Word(Jas.1:18;1Pet.1:23),
it is clear that being born of water means being born again by the Word of God.
