I will give you the keys of the kingdom of heaven

When Peter realized that Jesus is God in a human body – “the Christ, the Son of the living God” – Jesus told him He would give him the keys of the kingdom of heaven.

"And Jesus answered and said unto him, Blessed art thou, Simon Barjona: for flesh and blood hath not revealed it unto thee, but my Father which is in heaven." - Matthew 16:17

"And I will give unto thee the keys of the kingdom of heaven…" - Matthew 16:19a

Jesus had spoken to Nicodemus of the kingdom of God. (“The kingdom of heaven” is interchanged with “the kingdom of God” e.g., Mark 10:14 and Matthew 19:14).

"Jesus 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." - John 3:5

While Jesus made it clear we must be born of water and of the Spirit to enter the kingdom of God, He did not give specifics. Jesus gave Peter the keys as to how exactly we are born again. Peter revealed this on the Day of Pentecost after he received the Holy Ghost.

"And when the day of Pentecost was fully come, they were all with one accord in one place. ... And they were all filled with the Holy Ghost, and began to speak with other tongues, as the Spirit gave them utterance." - Acts 2:1, 4

When the people asked, “What meaneth this?” Peter preached the gospel, letting them know they had crucified their Messiah, the One they had been waiting for.

"Now when they heard this, they were pricked in their heart, and said unto Peter and to the rest of the apostles, Men and brethren, what shall we do?" - Acts 2:37

"Then Peter said unto them, Repent, and be baptized every one of you in the name of Jesus Christ for the remission of sins, and ye shall receive the gift of the Holy Ghost." - Acts 2:38

Peter made it perfectly clear what Jesus meant when He said a man must be born of water and of the Spirit. The keys to the kingdom of heaven are to repent, to be baptized by immersion in water in the name of Jesus Christ for the remission of sins, and to receive the gift of the Holy Ghost.

We now understand exactly what we must do.