K001. Why is the gospel of Jesus Christ the gospel of the kingdom of God?

K001. Today we are still in the era of preaching the gospel that Jesus preached
His words are still as effective as they were two thousand years ago. I will be starting a new series of discussion starting from K001. His words are the main theme of my discussion series starting from K001.
Of course, the gospel that Paul preached is the gospel that Jesus preached; but the gospel that Jesus preached is not just the gospel that Paul preached. The gospel that Jesus preached is more than what Paul could preach. It is also the gospel of the kingdom of God:

1. Mat 4:23 KJV  And Jesus went about all Galilee, teaching in their synagogues, and preaching the gospel of the kingdom, and healing all manner of sickness and all manner of disease among the people.
2. Mat 9:35 KJV And Jesus went about all the cities and villages, teaching in their synagogues, and preaching the gospel of the kingdom, and healing every sickness and every disease among the people.
3. Mat 24:14 KJV And this gospel of the kingdom shall be preached in all the world for a witness unto all nations; and then shall the end come.
4. Mar 1:14 KJV Now after that John was put in prison, Jesus came into Galilee, preaching the gospel of the kingdom of God,
5. Mar 1:15 KJV And saying, The time is fulfilled, and the kingdom of God is at hand: repent ye, and believe the gospel.

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