On earth, the kingdom of God comes into the lives of God's people. When asked by a bunch of teachers of the Law, "Where is this kingdom that you're talking about?" Jesus basically said: You know what? The kingdom is inside of you. The rule and reign of God begins in you—with you saying "yes" to God.
Whenever you think God is speaking to you—through his Word, through a prompting of the Spirit, through a circumstance, through a friend, through the guise of the ordinary or the disguise of the least of these—whenever you believe God is speaking to you, let Yes, God rise instinctively from your heart.
A lot of us who claim the name of Jesus Christ actually have a default mode, which is No, God. We see this in the life of Peter, who was foundational to the church, and yet he had a default mechanism of "No, Lord." In Matthew 16, Jesus says to his disciples, "Who do people say that I am? … Who do you say that I am?" Peter answers: "You're the Lord. You're the Messiah. You're the Savior of the world." Seeing his disciple's faith, Jesus then unfolds to his followers all that is going to happen to him—how he will be betrayed and handed over to the teachers of the Law who will beat, mock, and kill him. But three days later he will rise from the dead. And what does Peter do when he hears all of this? He pulls Jesus aside and rebukes him: "Never, Lord. This shall never happen. No, Lord."
Another instance when Peter says "No, Lord" is in the Book of Acts. He's fasting and goes on the rooftop to pray. God gives him a vision of a blanket coming down holding all the things that the Jewish diet deems unclean—food Peter believes he is not supposed to eat. And God keeps lowering this blanket to say to Peter that the gospel is to reach outside of the Jewish faith—that the gospel is not strictly on Jewish terms anymore. This is a radical message. And what does Peter say to God when he sees this vision? "Surely not, Lord."
We need to knock that habit out of ourselves to participate in God's kingdom. We need to get into the position and posture of saying Yes to whatever God is asking. Consider a forty-day experiment with this. Let's look at the significance of forty days biblically.
How many years was Israel wandering in the desert? Forty.
How many days did Moses stay up on the mountain to meet with God while he fasted and prayed and interceded for the people of Israel? Forty.
How many days was Israel deadlocked in battle with the Philistines while every day the big giant Goliath came up and taunted them until David stepped up to challenge him? Forty.
How many days did Noah sail the seas as God started his plans for the earth all over again? Forty.
How many days did Elijah travel to the mountain of Gath? Forty.
How many days was Jesus in the desert? Forty.
- And how many days did Jesus walk with his disciples after his resurrection so that he could teach them about the kingdom of God? Forty.
The Bible has always known what modern psychology has only discovered. It takes forty days to change your mind. If you have an entrenched way of seeing, of thinking, of responding, that's called a habit; it takes forty days to dismantle an entrenched way of seeing and thinking and responding and replace it with a new way.
So for the next forty days practice saying Yes, God. Not so that after forty days we can go back to No, God, but because it takes forty days pushing in the opposite direction of what is habitual to us—forty days of pushing in the opposite direction to establish a new way of thinking and seeing and responding.