As we search the Scriptures, it becomes apparent that there has only ever been one gospel, not two. We are told, in fact, that it was first preached to Abraham.
The promises to Abraham included land and abundance in physical categories, as well as spiritual blessings. The fact that we have the same promise of blessings as Abraham is shown in verse 29.
The definition of the Gospel of the Kingdom, built on the promises to Abraham, is found throughout the Old Testament, as we shall see. In the Gospels, John the Baptist, Jesus, and all of his disciples preached the Kingdom of God, as we saw in a previous article. In fact, Jesus said preaching the kingdom was the whole reason he was sent in Luke 4:43, as we also saw in that article. The book of Acts ends with Paul continuing to preach the kingdom of God (Acts 28:30,31). There is nothing to indicate that there was a change in the gospel message that the followers of Jesus were to preach.
It has been said that the gospel that Paul preached was not the same gospel that Jesus preached. I was taught that Paul's gospel was different, because Jesus spoke of the kingdom, but Paul preached "the gospel of grace."
However, the very next verse defines what the gospel of grace is.
And in verse 27 he equates that Gospel of the Kingdom of God with the whole purpose, or counsel, of God.
Unless Paul preached two different gospels, it is clear that the Gospel of the Kingdom of God is the Gospel of Grace, which is all the counsel of God. It could not be a new gospel, for when Paul was giving his defense in Jerusalem in Acts 24, he says:
I was taught that the promises to Israel as written in the Law and the Prophets were different from the Christian hope, yet Paul said he preached the same things that were promised to Israel.
The gospel Paul preached and the hope of the promise made to the fathers are the same gospel, and it was that message for which he was accused of the Jews. At the end of the book of Acts, nothing had changed as far as what gospel Paul preached.
Paul refers to the kingdom of God in his epistles as well (Romans 14:17; I Corinthians 4:20; 6:10; 15:50; Galatians 5:21; Colossians 4:11; II Thessalonians 1:5), so his gospel can't be different from that which Jesus preached. He criticized the Galatians for being swayed by "another gospel" and said, "But though we, or an angel from heaven, preach any other gospel unto you than that which we have preached unto you, let him be accursed" (Galatians 1:8).† If what he wrote about in his epistles was different from the Gospel of the Kingdom which he preached all through Acts, he would have been under his own curse. But in I Timothy 6:3-4, he states that we are to consent to the wholesome words of Jesus Christ.
I once believed that what Jesus taught concerning the Kingdom of God was addressed to Israel, and thus fulfilled the Old Testament prophecies, while the gospel that Paul and the apostles preached concerned the Great Mystery, which was not revealed in the Old Testament or in the time of Jesus Christ. If this is true, then why did Paul quote from the Old Testament so much? In Acts he preached the gospel, reasoning from the Scriptures (Acts 17:2; 18:28; 28:23). All throughout his epistles he constantly referred to Old Testament scriptures, as the foundation for his doctrine.
"By the scriptures of the prophets" is the Old Testament scriptures. He cited many, many quotations from the Old Testament in his writing and public preaching. Why did Paul use the Old Testament so much if the Mystery was not revealed there? To understand this we must consider what is meant by a mystery. A mystery is not something that was never even mentioned, but rather something that was not understood. There is something to be seen or observed, or something spoken, but it is not understood by those who observe it. In Daniel, chapter 2, King Nebuchadnezzar has a dream which he wants interpreted. It is referred to as a "secret".
In the above verses, the word for "secret" in the Septuagint (the Geek translation of the Old Testament) is the word musterion which is the same word that is translated "mystery" in the New Testament. The dream was a mystery, because the understanding of its meaning was hidden.
Jesus told his apostles that it was given to them to know the mysteries of the kingdom, but to others he spoke in parables (Luke 8:10). The mysteries of the kingdom were not things that were never spoken, but things that were not understood when spoken, the result being that "...seeing they might not see, and hearing they might not understand." There were also a number of things the apostles themselves did not understand at first. When Jesus first began to speak of his death and resurrection, they didn't get it at all.
Now when we read of Jesus being delivered into the hands of men and killed, we have no trouble understanding it, do we? Yet the disciples did not understand it, for it was hidden. Many of the things they saw and heard they did not understand at the time, but later it became clear.
God often said things through the Prophets that were not understood at the time they were spoken (many times even by the Prophets who spoke them). But later they were revealed after Jesus Christ fulfilled them. Until after it was accomplished, it was not understood how the suffering and death of the Messiah fit into the plan to bring God's rule to earth, and how the Mosaic Law was then fulfilled and completed. It was also not understood that a period of time would intervene between his first coming and his second, during which the nature and power of the Kingdom could be experienced in a limited form. And while it was said in many places in the Old Testament that the Gentiles would be blessed through Israel, it was never understood how they would be blessed, nor was it ever imagined that the Gentiles would be "fellowheirs, and of the same body, and partakers of his promise in Christ by the gospel." (Ephesians 3:6). These mysteries of the Kingdom were hinted at in the Old Testament, but their full meaning was not understood until it was revealed to Paul, who then wrote about it in his epistles. This will be discussed in further detail in Mysteries of the Kingdom.
Paul wrote at length about what Jesus had accomplished by his suffering and death. But he did not imply that the result of Christ's sacrifice was a new gospel, different from the Gospel of the Kingdom which Jesus had preached. For many years, I am ashamed to say, I rarely read the Gospels, because I believed they were not addressed to me.
The good news of God's Kingdom is the one Gospel that ties together the entire Bible. The details concerning what Messiah's sacrifice accomplished, how that fits into the overall plan, and what we have during this period of time as a foretaste of the coming Kingdom, are what Paul wrote about in his epistles. But they are added details; they do not constitute a new or different gospel. The death and resurrection of Jesus are absolutely fundamental to our gaining entrance into God's Kingdom, but we must take care not to limit our definition of the Gospel to the death and resurrection, and neglect the full message concerning that Kingdom.