Nicodemus, in John 3:1, like the rich young ruler who came to Jesus in Mark 10:17, was a ruler of the Jews. Though a Pharisee, trained from young to keep the law, he had the same struggle as the man in Mark 10:17, which caused him to seek out Jesus one night, for Jesus’ miracles had convinced him that Jesus was from God.
Discerning Nicodemus’ struggle, Jesus straightaway told him, “Unless one is born again he cannot see the kingdom of God” (John 3:3). But “How can a man be born when he is old (v 4)?” Nicodemus asked. To this, we may refer him to Jesus’ reply in Mark 10:27 “With man it is impossible, but not with God. For all things are possible with God.”
The Lord Jesus then explained to Nicodemus in John 3:5-8 how this new birth is the work of God, the invisible and mysterious work of the Holy Spirit. This means to enter the kingdom of God requires a spiritual rebirth. For “The natural person does not accept the things of the Spirit of God, for they are folly to him, and he is not able to understand them because they are spiritually discerned” (1 Cor. 2:14).
Ephesians 2:1-2 explain that this spiritual condition is because “you were dead in the trespasses and sins in which you once walked, following the course of this world, following the prince of the power of the air, the spirit that is now at work in the sons of disobedience.” We were dead to the things of God—dead in sin!
To make us alive from this spiritual deadness, the work of regeneration is needed. Hence Titus 3:5 tells us, “He saved us . . . by the washing of regeneration and renewal of the Holy Spirit.” The Holy Spirit regenerates us, bringing us to life by creating a new heart in us through His indwelling (Ezek. 36:26). We become a new creation (2 Cor. 5:17), with new desires for the things of God, like a newborn child that hungers after God and His word (1 Pet. 2:2).
From those led by “the spirit that is now at work in the sons of disobedience,” we become those who are led by the Spirit of God, whom we received as “the Spirit of adoption as sons, by whom we cry, ‘Abba! Father (Rom. 8:14-15)!’ ” Romans 8:16-17 then tells us this Spirit of God will bear witness with our inner spirit that we are the sons of God, heirs of His glorious promises, as evident in our willingness to suffer for His name sake, promising us the glory to come. This is the blessedness of new birth, another explication of Mark 10:17-31.