Let us look at the Lord Jesus' words here:
"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. That which is born of the flesh is flesh; and that which is born of the Spirit is spirit. Marvel not that I said unto thee, Ye must be born again. The wind bloweth where it listeth, and thou hearest the sound thereof, but canst not tell whence it cometh, and whither it goeth: so is every one that is born of the Spirit" (Jn.3:5-8).
Robert V. McCabe writes that
"in v. 5 the preposition 'ek' governs two nouns, 'hydor' and 'pneuma,' that are coordinated by 'kai.' This indicates that Jesus regards 'hydor kai pneuma' as a conceptual unity. If 'hydor kai pneuma' is a conceptual unity, this phrase may be taken either as a 'water-spirit' source or a 'water-and-Spirit' source of birth. A good case can be presented for either view in the context of John 3:1–8. With either view, there is one birth that is characterized either as 'water-spirit,' or 'water-and-Spirit.' Neither of these understandings suggest that there are two births, physical and spiritual" [
emphasis added] (McCabe, "The Meaning of 'Born of Water and the Spirit' in John 3:5,"
Detroit Baptist Seminary Journal [Fall 1999], p.85-107).
There is only one birth being spoken of here and in verse 3 the Lord Jesus refers to this birth as being "born again." And here Peter tells us exactly how a person is "born again":
"Being born again, not of corruptible seed, but of incorruptible, by the word of God...And this is the word which by the gospel is preached unto you" (1 Pet.1:23,25).
A person is born again by the gospel. So the word "water" in this verse is obviously used in a typological sense by the Lord Jesus:
"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. That which is born of the flesh is flesh; and that which is born of the Spirit is spirit. Marvel not that I said unto thee, Ye must be born again. The wind bloweth where it listeth, and thou hearest the sound thereof, but canst not tell whence it cometh, and whither it goeth: so is every one that is born of the Spirit" (Jn.3:5-8).
It is clear that the word "water" is used in a typical sense where the "water" stans for the "word" and we read the following verse which proves this typological relationship:
"Husbands, love your wives, even as Christ also loved the church, and gave himself for it; That he might sanctify and cleanse it with the washing of water by the word" (Eph.5:26).
The gospel comes in the power of the Holy Spirit (1 Thess.1:5) and it is that "word" which results in the birth of the Spirit. The Lord Jesus said:
"It is the spirit that quickeneth; the flesh profiteth nothing: the words that I speak unto you, they are spirit, and they are life" (Jn.6:63).