Because of Christ's rejection by Israel and the Gentiles, the entire world is guilty before God. In grace, He has begun something new, something which in the past ages had been a secret and still is to the professing masses of Christendom (Eph. 3:4-64Whereby, when ye read, ye may understand my knowledge in the mystery of Christ) 5Which in other ages was not made known unto the sons of men, as it is now revealed unto his holy apostles and prophets by the Spirit; 6That the Gentiles should be fellowheirs, and of the same body, and partakers of his promise in Christ by the gospel: (Ephesians 3:4‑6)). We speak of the kingdom of heaven. Man's blessing depends on the death and resurrection of Christ who as man has entered into the heavens; hence, His kingdom is now the kingdom of the heavens.
This present kingdom of heaven does not hinder God from fulfilling His promise to Abraham in a future day (Gen. 17:1-81And when Abram was ninety years old and nine, the Lord appeared to Abram, and said unto him, I am the Almighty God; walk before me, and be thou perfect. 2And I will make my covenant between me and thee, and will multiply thee exceedingly. 3And Abram fell on his face: and God talked with him, saying, 4As for me, behold, my covenant is with thee, and thou shalt be a father of many nations. 5Neither shall thy name any more be called Abram, but thy name shall be Abraham; for a father of many nations have I made thee. 6And I will make thee exceeding fruitful, and I will make nations of thee, and kings shall come out of thee. 7And I will establish my covenant between me and thee and thy seed after thee in their generations for an everlasting covenant, to be a God unto thee, and to thy seed after thee. 8And I will give unto thee, and to thy seed after thee, the land wherein thou art a stranger, all the land of Canaan, for an everlasting possession; and I will be their God. (Genesis 17:1‑8)). In God's time there will be a kingdom on earth in power and glory. It will be spoken of as the kingdom of the Son of man.
There are four parts to the ministry of the kingdom in Matthew: •The three-and-one-half years of the public ministry of the Lord Jesus while on the earth.
•The present two thousand years, when Jesus, the King, is in heaven and the Spirit of God is acting through His servants on earth.
•The period after the rapture of the Church when the remnant of Israel, having returned to their own land, preach in Jerusalem for three-and-one-half years and later to the nations of the whole prophetic earth for the last three-and-one-half years, to the close of the great tribulation.
• The millennial day when Christ will be present on earth to order His kingdom, and the gospel will be preached until "the earth shall be full of the knowledge of the Lord, as the waters cover the sea." Isa. 11:99They shall not hurt nor destroy in all my holy mountain: for the earth shall be full of the knowledge of the Lord, as the waters cover the sea. (Isaiah 11:9).
Being lost, man's acceptance by God no longer depends on his efforts, but it depends on God's pure mercy to those who, humbling themselves in repentance and confessing their sins, enter the kingdom of heaven.
In Matthew's gospel, as we follow the Lord, the King, humbly serving the Father, we see principles in His ministry that are entirely new, which characterize His kingdom, morally, both during His absence from earth and when He returns for the millennium.