In a stage play, in order to bring the audience to where the play takes place, the stage has to be set. I once played James Keller, brother of Helen Keller, in a production of The Miracle Worker. The play was being produced in a former courthouse in Queens and, as you might imagine, this building had no stage. So, we built a stage, and not just any old stage, but one that had several levels. Once the stage was built, we then "set the stage," preparing and decorating it for the various scenes in the play, so that each of those levels became a specific part of the Keller home.
To set the stage for something can also mean to be a catalyst for something that will happen later. Galatians 4:4 says that when the fullness of time had come, when the time was right, God sent His Son, Jesus, to be born of a woman. In other words, for the time to be right for God to send His Son, the promised Messiah who would deliver us from sin, the stage had to be set. All the pieces had to be in place so that the time would be right for Jesus to come into the world and secure freedom from sin for each and every one of us. But, what made it the right time?
That Jesus had to come was unquestionable. Sin had corrupted the world and separated man from God. Through the prophets, God promised to send a Messiah. The prophecies spoke of a child being born of a virgin and even pointed to Bethlehem as the place where the Messiah would be born. The prophecies spoke of the suffering servant pointing to the fact that Jesus would suffer and die for us. But the prophecies did not say when this would happen.
The period of time between the voice of the last Old Testament prophet and the beginning of the New Testament was about 400 years. Many things took place during that time, things that set the stage for the Messiah. Israel fell under the rule of two different empires, first the Greeks, then the Romans, both of whom had a tremendous effect on the Jews.
Greece had a great influence on the culture of not only Israel, but also of the world, and Rome provided a strong legal and political force. Because of this, the time into which Jesus was born was a time of peace and a time in which travel and communications were better than ever. This made it the perfect time for God to send Jesus into the world, as the gospel message that would be preached after His ascension into heaven could be spread much more easily during that time than at any other time before it.
The time when God sent Jesus was also the perfect time because of the religious system that was in place in Israel. Before this time, the most influential men in Israel were the priests. But, when Jesus came, it was the Pharisees who were more influential. The Law and the traditions of men were of great importance to the Pharisees. And the priests, the Sadducees, were more concerned with wealth and position than with God's purposes for them. These leaders had lost touch with God's plan and, as a result, they were not ready to accept Jesus for who He was.
These were some of the things that had to be in place in order to "set the stage" for the coming of the Savior. And so, in the fullness of time, on that night in Bethlehem, a virgin named Mary gave birth to the baby who would become the Savior of the world.