John Piper comments on Luke 1:
The first thing Gabriel reveals about Jesus is that “He will be great” (1:32). This Jesus is going to be a great man. That is the first thing Theophilus needs to hear about Jesus. You may have never heard of Nazareth, Theophilus, and this young girl may be poor and obscure, but don’t judge by merely human outward appearances. Her son is going to be great. You no doubt have studied the lives of many great men in Greek and Roman history. But do not be deceived Theophilus: “What is exalted among men is an abomination in the sight of God” (Luke 16:15). In spite of all appearances to the contrary, this son of Mary is going to be great. Come with me, Theophilus. In this gospel we are setting out on a journey towards a new view of greatness. Don’t judge prematurely. Give yourself time for this man to prove himself. It is not easy for you, a noble Roman official, to comprehend a statement like, “He who is least among you all is the one who is great” (Luke 9:48). But it is true, and Jesus himself will prove it to you, if you listen now to what I have to say and then watch how he lives and teaches. This Jesus is going to be great. Now learn greatness from him.
Knowing God through His Word ... Day by Day 
Praise God for His Word, which instructs, convicts and comforts. We are wisest when we heed Him.