"The kingdom of God" in Matthew 21:43 refers not to the future establishment of Christ's Kingdom on earth, but to a dominion then in existence.
The context of this parable begins in Matthew 21:23, indicating that its audience was “the chief priests and the elders of the people.” Verses 45-46 show their reaction:
Now when the chief priests and Pharisees heard His parables, they perceived that He was speaking of them. But when they sought to lay hands on Him, they feared the multitudes, because they took Him for a prophet. (Emphasis ours throughout.)
Even though God had not given the religious leaders the means to understand all the mysteries of the Kingdom (Matthew 13:11), they could still perceive that Jesus aimed several of His teachings directly at them.
The chapter break obscures that Jesus continued speaking to the same leaders in the Parable of the Wedding Feast (Matthew 22:1-14), another parable of “the kingdom of heaven” (verse 2). The king sends out invitations to the feast in batches. The first two sets are declined, signifying the response of the physical nation of Israel. Only after the “king . . . sent out his armies, destroyed those murderers, and burned up their city” (verse 7)—foreshadowing Jerusalem's destruction forty years after they rejected the gospel of the Kingdom—does a third call go out, and his servants find suitable guests for the wedding.
This third group of guests represents those whom Christ later gave, not only entrance to the wedding feast, but also authority to rule. As He had earlier told Peter, a representative of the spiritual nation, “I will give you the keys of the Kingdom” (Matthew 16:19). The stewardship of the Kingdom would be transferred.
Likewise, Jesus foretold of a future time when His followers would receive greatly increased authority: “Assuredly I say to you, that in the regeneration, when the Son of Man sits on the throne of His glory, you who have followed Me will also sit on twelve thrones, judging the twelve tribes of Israel” (Matthew 19:28). Even as Jacob supplanted Esau, so God would make certain that Jacob's descendants would likewise be supplanted (though not forgotten) because of their unfaithfulness.
In these two parables, we can see a critical facet of God's dominion. Jesus considered the chief priests, the elders, and the Pharisees part of God's Kingdom, and also certified that they would have the Kingdom taken from them. They, like tenant-farmers, had a measure of responsibility over that national Kingdom because of their leadership positions within it. They wielded religious power that Jesus acknowledged (Matthew 23:2-3), which had its source in God (Romans 13:1).
In the Parable of the Wicked Vinedressers, the vineyard is the Kingdom of God, and the vinedressers are those tasked with attending to it. Jesus prophesied that stewardship would be transferred because the original caretakers had proven themselves unfaithful. Psalm 80:8-19 also represents the Kingdom of Israel as a vineyard (as does Isaiah 5:1-7), and the shared symbol confirms that the Kingdom of Israel was the Kingdom of God at that time, though not in its fullness.
Similarly, the Parable of the Wedding Feast, though a parable of the “kingdom of heaven,” deals at length with Israel, specifically Judah. It illustrates the physical descendants of Abraham as not acting like Abraham at all (see John 8:30-38). God told Israel even before she made the covenant, “You shall be to Me a kingdom of priests and a holy nation” (Exodus 19:6), revealing that His original intent for Israel was to be a Kingdom.
Israel's first human king, Saul, was unfaithful, and the Kingdom was taken from him and given to David. After the people contributed for the Temple, David praised God, saying, “For all that is in heaven and in earth is Yours; Yours is the kingdom, O LORD, and You are exalted as head over all” (I Chronicles 29:11). Similarly, Abijah refers to the house of David as “the Kingdom of the LORD” (II Chronicles 13:8). Both Asaph and Isaiah proclaim that God was still Israel's King, even though earlier the nation had requested a king “like all the other nations,” rejecting God (Psalm 74:12; Isaiah 33:22; see I Samuel 8:4-8; Deuteronomy 17:14). The Kingdom of Israel was an aspect of the basileia—the sovereign dominion—of God. It was a Kingdom with its origin and authority in heaven.
David C. Grabbe
God's Kingdom in the Parables (Part One)