1. Jesus was very familiar with the Kingdom of heaven. It was and is His true home.
In the beginning was the Word, and the Word was with God, and the Word was God. He was in the beginning with God (John 1: 1-2).
2. He entered a religious system that had almost completely distorted the truth. As the representative of the Kingdom, Jesus wanted to set the record straight.
Woe to you, blind guides, who say, “Whoever swears by the temple, it is nothing; but whoever swears by the gold of the temple, he is obliged to perform it.”
Fools and blind! For which is greater, the gold or the temple that sanctifies the gold? And, “Whoever swears by the altar, it is nothing; but whoever swears by the gift that is on it, he is obliged to perform it.” Fools and blind! For which is greater, the gift or the altar that sanctifies the gift? Therefore he who swears by the altar, swears by it and by all things on it. He who swears by the temple, swears by it and by Him who dwells in it. And he who swears by heaven, swears by the throne of God and by Him who sits on it (Matthew 23: 16-22).
3. He needed to change the end times theology of the Jews. All of the Jews expected the coming Kingdom and the coming King. They’d been waiting for hundreds of years. Many were sincerely wrong about who and how their king would be; they had misinformed expectations. They weren't expecting a suffering Messiah. Jesus had to clean up their theological end times mess.
4. A clear understanding of the keys of the Kingdom would help His followers implement Kingdom realities here on earth. This was Jesus’ intention from the beginning.
Your Kingdom come. Your will be done on earth as it is in heaven (Matthew 6: 10).
5. Teaching them the keys of heaven would help the believers to see God as their Father, instead of as a cruel tyrant.
In this manner, therefore, pray: Our Father in heaven, hallowed be Your name (Matthew 6: 9).
Jesus was concerned about our relationship with God:
If you had known Me, you would have known My Father also; and from now on you know Him and have seen Him (John 14: 7).
The concept of God being a Father to a believer was revolutionary to the Jews. In Matthew 16, Peter made a realization and confession that would forever change his life.
He said to them, “But who do you say that I am?”
Simon Peter answered and said, “You are the Christ, the Son of the living God” (Matthew 16: 15-16).