The Old Testament was complete by about 400BC, with Esther, Nehemiah and Malachi being among the last books chronologically. Yet the New Testament doesn’t start until after Christ was born, four centuries later. Why do we have a gap in between? Did God change His mind and lose interest?
The Jews were told that there would come a period of darkness and a time of no visions from God. This was their own fault: they had turned their back on God. “Therefore you shall have night without vision, and you shall have darkness without divination. The sun shall go down on the prophets, and the day shall be dark for them.” (Micah 3v6) “‘Behold the days are coming, says the Lord God, ‘That I will send a famine on the land, not a famine of bread, nor a thirst for water, but of hearing the words of the Lord.'” (Amos 8v11)
Even contemporary history, such as the Apocryphal books of the Maccabees, show that this happened: “Thus there was great distress in Israel, such as had not been since the time that prophets ceased to appear among them.” (1 Maccabees 9v27 – not inspired Scripture but a useful record in this context)
Yet God had always planned to send a Messiah to redeem His people. He did not suddenly change His mind. The Old Testament is full of prophecies about him (you might like to read Isaiah 53), and Daniel’s prophecy even counts down the time until his appearing, which explains why certain wise men were expecting his arrival at the right time. “Know therefore and understand that from the going forth of the command to restore and build Jerusalem until the Messiah the Prince, there shall be seven sevens and sixty-two sevens,” (Daniel 9v25 – this is often interpreted as 69 x 7 years between the two events, which is correct).
So the Israelites needed to learn their lesson. They had to appreciate that their actions of unbelief and moral depravity had consequences – a period of spiritual darkness with no direct vision or message from God. But surely He was also waiting until the time was right in another sense. We might consider that at the time Jesus was teaching and shortly after, the Roman Empire made long distance travel and easy communication possible for the first time. This made the spread of Christianity much easier – the world had certainly changed a lot since the Bible’s Dark Ages of the centuries before.