“But now, since you didn’t believe what I said, you will be silent and unable to speak until the child is born.” (Luke 1:20)
A teenager once asked me this thoughtful question about Christmas: “Since there was so much hype about the birth of Jesus Christ, why is it that thirty years later nobody seemed to believe in Him? You would think everyone would have just been waiting for Him to begin His ministry!”
Actually, there were only a handful of people who knew about that first Christmas. The first one to know was a priest named Zechariah. He and his wife Elizabeth were godly people, very advanced in years. They had no children and the angel Gabriel told Zechariah that he and his wife were going to have a child who would be the last of the prophets to tell us about the coming of the Messiah. Their son, whom they were to call John, would actually point at Christ and introduce Him to this world.
Zechariah did not believe the angel. He was therefore told that everything he had heard was going to happen, but he would be smitten mute and not be able to tell anyone until his child was born. This priest had the greatest sermon to preach that any priest ever had. God was going to intersect human history! But he could not preach it because of his unbelief.
Before you are too hard on Zechariah, let me ask you a question. The New Testament tells us more than three hundred times that God is going to intersect human history a second time when Jesus Christ comes back again. Have you ever told anybody about that Christmas to be?
Or does your unbelief shut your mouth?
4SpiritualSecrets 
Wow. That last line goes right to the heart of it!