Baptism is recognition of a spiritual status. John baptised those who had repented, meta noia-ed, changed their mind, about living selfish lives, and had agreed with God that living selflessly was better, for the long view. That's why John demanded that candidates manifest fruit consonant with repentance. In other words, they had left selfish living, closed the door to the world with flood waters, like Noah, like Israel after crossing the sea, giving rise to the sobriquet, born of water.
Matthew 3:7But when he saw many of the Pharisees and Sadducees coming for baptism, he said to them, “You brood of vipers, who warned you to flee from the wrath to come? 8“Therefore bear fruit in keeping with repentance; 9and do not suppose that you can say to yourselves, ‘We have Abraham for our father’; for I say to you that from these stones God is able to raise up children to Abraham. 10“The axe is already laid at the root of the trees; therefore every tree that does not bear good fruit is cut down and thrown into the fire.
However, he recognised that repentance was a stage, that it preceded redemption. In relation to God's words, repentance was acknowledgement that selfless living was better, but was also belief that God had planned for a better humanity, a better city, a new man in Christ, where living selflessly could be safe, and not only safe, but a fulfillment of God's promise to be a blessing to the world, by receiving the Holy Spirit.
Hebrews 11:13All these died in faith, without receiving the promises, but having seen them and having welcomed them from a distance, and having confessed that they were strangers and exiles on the earth. 14For those who say such things make it clear that they are seeking a country of their own. 15And indeed if they had been thinking of that country from which they went out, they would have had opportunity to return. 16But as it is, they desire a better country, that is, a heavenly one. Therefore God is not ashamed to be called their God; for He has prepared a city for them.
Galatians 3:13Christ redeemed us from the curse of the Law, having become a curse for us—for it is written, “CURSED IS EVERYONE WHO HANGS ON A TREE”— 14in order that in Christ Jesus the blessing of Abraham might come to the Gentiles, so that we would receive the promise of the Spirit through faith.
That is why Paul asked if the disciples in Ephesus had received the Holy Spirit. They had received John's baptism, but John had instructed them to believe in Jesus. For what? For the message, the Good News, that He was the fulfilment of the promise to Abraham.
Those who did so believe that Jesus was the fulfilment of the promise to Abraham, was the Christ, were marked with the baptism in the name of Jesus, the baptism of the Holy Spirit and fire, revelation and discernment. Like Peter and John. And even Judas, Simon the sorcerer, Ananias and Sapphira. But the Body of Christ, through fellowship, recognised that the last four were not "clean", not born again, like Caleb, who had had a different spirit.
Numbers 14:24 "But My servant Caleb, because he has had a different spirit and has followed Me fully, I will bring into the land which he entered, and his descendants shall take possession of it.
Caleb remembered God's great works, and let the lessons, the conclusions take root, and grow, so that he had surplus faith, like the wise virgins. So when he heard God's voice (when the bridegroom arrived, when the feast was spread in the desert) , he was not like the rest of Israel, who disobeyed because of unbelief, and would not manifest a great work in their own lives, so that people like Rahab could be blessed, when they saw God was with person. Short of entering the Kingdom of God, the giving of the Spirit, towards being a blessing to the whole world.
Psalms 78:18Then they spoke against God; They said, "Can God prepare a table in the wilderness?
Matthew 22:11“But when the king came in to look over the dinner guests, he saw a man there who was not dressed in wedding clothes, 12and he said to him, ‘Friend, how did you come in here without wedding clothes?’ And the man was speechless. 13“Then the king said to the servants, ‘Bind him hand and foot, and throw him into the outer darkness; in that place there will be weeping and gnashing of teeth.’ 14“For many are called, but few are chosen.”
John 3:1 Now there was a man of the Pharisees, named Nicodemus, a ruler of the Jews; 2this man came to Jesus by night and said to Him, “Rabbi, we know that You have come from God as a teacher; for no one can do these signs that You do unless God is with him.” 3Jesus answered and said to him, “Truly, truly, I say to you, unless one is born again he cannot see the kingdom of God.”
Acts 4:13 Now as they observed the confidence of Peter and John and understood that they were uneducated and untrained men, they were amazed, and began to recognize them as having been with Jesus.
Baptism of water provides a clean conscience, a clearance, to those who have agreed with God that it is better in the long view to be selfless, this averting God's wrath, but without seeing God's promise, true even of John the Baptist, the greatest of those born of a woman.
Baptism of the Holy Spirit provides the giving of the Holy Spirit and fire, revelation and discernment, drink from the Rock, but unless one is born again, has allowed the revelation to take root, grows faith, builds with gold and silver and precious material, one will not be ready to manifest God's great works in his or her own life, have oil for lamps, posses wedding garments, when one hears His voice, to feast, to bring forth living waters.
Hebrews 4:1Therefore, let us fear if, while a promise remains of entering His rest, any one of you may seem to have come short of it. 2For indeed we have had good news preached to us, just as they also; but the word they heard did not profit them, because it was not united by faith in those who heard.
3For we who have believed enter that rest, just as He has said,
“AS I SWORE IN MY WRATH,
THEY SHALL NOT ENTER MY REST,”
although His works were finished from the foundation of the world.
4For He has said somewhere concerning the seventh day: “AND GOD RESTED ON THE SEVENTH DAY FROM ALL HIS WORKS”; 5and again in this passage, “THEY SHALL NOT ENTER MY REST.” 6Therefore, since it remains for some to enter it, and those who formerly had good news preached to them failed to enter because of disobedience,
7He again fixes a certain day, “Today,” saying through David after so long a time just as has been said before,
“TODAY IF YOU HEAR HIS VOICE,
DO NOT HARDEN YOUR HEARTS.”
8For if Joshua had given them rest, He would not have spoken of another day after that. 9So there remains a Sabbath rest for the people of God. 10For the one who has entered His rest has himself also rested from his works, as God did from His. 11Therefore let us be diligent to enter that rest, so that no one will fall, through following the same example of disobedience.
Or at least be ready to ask for terms of peace.
Due diligence, people. Do your homework. Look for recurring motifs, parallel teachings.
To answer, being born of water is being born after the flood water of repentance closes the ways of the world behind us. So the disciples were born of water at the time they were baptised, were recognised to have changed, by John the Baptist.
All Scripture from the NASB.