For me, The Kingdom of heaven and born again were very curious and important topics.
For such a high school student, a bible class teacher taught me that it was like a function of mathematics, which remained a more difficult puzzle for a long time.
A similarl curious law teacher, Nicodemus, visited Jesus at night. Jesus resolutely said that if we are not born again, we cannot see the kingdom of God (John 3: 3).
He was reproved because he understood born again as entering and exiting the mother’s womb. The truth was that he would die in the world of Satan’s reign and be reborn on the world of God’s reign. Jesus later said that he would open the door with the key and enter into the kingdom of heaven. There is a kingdom where God’s rule is realized through Christ.
Simon Peter answered and said, You are the Christ, the Son of the living God. (Mat.16:16)
And I will give unto you the keys of the kingdom of heaven ~on earth~ in heaven~ (Mat.16:19)
Confession on Jesus as the Christ was given as the key to the kingdom of heaven.
Woe unto you, lawyers! for you have taken away the key of knowledge: you entered not in yourselves, and them that were entering in you hindered. (Luk.11:52)
The key to enter kingdom of heaven is the knowledge that Jesus is the Christ (Anointed King, Priest, and Prophet).
For this knowledge makes one enter into the reign of God. In other words, they become the people of the kingdom of God through the priest, the prophet, and the king system. Therefore, based on that knowledge, it is the use of the key to make a proper response to each part of Christ. You can be led by the prophet Jesus and forgiven through the priest Jesus.
It is to receive Jesus as the King of His kingdom.(John1:11) And by obedience, they live their lives as a people in the king’s reign.
This is called as born again that dies and lives again because of dying as a people of the kingdom of darkness and being reborn as a people of God’s kingdom. If the knowledge of this information is not conveyed correctly, he can be a blocker to the gate of the kingdom of heaven, like a lawyer who prevents him from entering the kingdom of heaven.
To open their eyes, and to turn them from darkness to light, and from the power of Satan unto God, that they may receive forgiveness of sins, and inheritance among them which are sanctified by faith that is in me. (Acts 26:18)