Luke was deliberate in writing his gospel - he wanted to get the facts down in an orderly account. He did his research and consulted eye-witnesses. Luke was conscious of a Big Thing going on, and he wanted to record it: the person Jesus Christ had changed things, Big Time.
The historic details are invaluable for us: they locate the story in world history. Yet this was not just another event on a global timeline, this was the next chapter in what God was doing in the world. God acts, and He acts through world history. The person of Jesus becomes the centre-piece in the Big Story of God.
The childless couple go up to the temple to worship. Zechariah is chosen for the special worship act inside the temple. Yet the routine becomes extraordinary as the angel appears: God is at work, even through the seemingly normal and random (remember they drew lots!).
Yet even with an angel in our face it is easy for us to look to human circumstances and doubt what God says to us. Zechariah doubts, and the outcome is that he is made mute. Hence the key question:
Do we dare to not believe what God tells us?
How mute are we as individuals or as a church because of our unbelief? God speaks, not necessarily through an angel, but in a variety of ways, yet we look to human factors, worry about what people might think, and side with unbelief. Surely we need to learn to both hear His voice and then go with it, knowing that God will accomplish His purposes, even in the ordinariness of our lives.
Thankfully God is gracious - He still works through Zechariah and his wife; the story moves on to John and then Jesus. In weeks to come we will learn what Jesus was about, and therefore what we should be about. God's plans unfold through Jesus and expand to include His followers. Those plans include you and me, no matter how 'ordinary' we may feel. Luke wrote so that others can believe, can become part of the extending story, of the ongoing plans of God changing world history.
You are called into what God is doing!