The word "kingdom" used in the New Testament is a strong term in the Greek. Some translators have advocated the use of "sovereignty" as its equivalent. The idea is one of sovereign rule, of kingly authority. Do you recall the words of Revelation 20:4 and 6? Both verses speak of the resurrected saints reigning with Christ for a thousand years. The word "reign" used in both verses comes from the same root as the word "kingdom." The kingdom of God is the reign of God; the kingdom of heaven is the reign of heaven. But what does this imply? Surely it is not difficult for us to understand. Before we were saved we were under the dominion of Satan, and outwardly our lives were governed by men. As children we were under the authority of our parents; as students we were under the authority of our teachers; as citizens we were under the authority of the state; but there was no divine authority in our lives.
Look at the modern cities. What order prevails! A white line runs along the middle of the road and controls the comings and goings. No one crosses that white line. When someone is about to drive in a certain direction, and he sees a notice indicating one-way traffic, he does not go that way. Elsewhere he sees "No Parking," so he does not park there. How orderly! But remove the government, remove the police, remove the law-courts, and see what the cities would look like! There would be utter chaos. Why is it that today people are so orderly? It is because the government, the police, and the law-courts are exercising control over them. Are they under the authority of God? No! And neither were we before we were saved. We were not under the rule of God, which means that we were not in the kingdom of God.
But one day, through the gospel, God came to us and said, "You must repent!" Repent of what? Not just repent of certain wrongs; not just repent of certain sins; but repent radically—repent of not being subject to the authority of heaven; repent of not submitting to the sovereignty of God.
The reason for our wrongdoing is primarily our nonacceptance of God's government. Men commit all kinds of sins because they will not let God exercise His authority over them. But how can He bring them under His authority? By means of the gospel! The gospel that the New Testament reveals is a gospel proclaimed to rebels—to men who have resisted God's authority, to men who have rejected His rule, to men who would not have Him to reign over them. That gospel cleanses such men and puts God's life within them so they can accept God's government. That is the New Testament gospel!
You have heard the gospel, you have believed and you have been saved, but have you seen that the gospel has brought you under the rule of God? Have you seen that you have been saved for this specific purpose, that you might come under His control? Have you seen that your salvation is not merely a question of pardon, peace, and life, but that the very object of your being forgiven and having life imparted into you, is to bring you under the sovereign rule of God? That is the gospel! Revelation 1:5-6 reads, "To Him Who loves us and has loosed us from our sins by His blood, and made us a kingdom." The reason God washed us in the precious blood was that we might be brought under His government.
As I have preached the gospel in different places, I have had personal contact with numbers of people who have been clearly saved and who after their salvation have said something like this to me: "How is it that ever since I was saved I seem to be under some sort of control? It seems as though someone has taken over the management of my life, so that when I want to do this or that, something in me says, 'You can't!' And when I want to do that it says, 'No! No!' Formerly I was my own master; now I can no longer do as I please. What does it all mean?"