Why Doesn't God Roar?

Phillip Yancey, in his book The Jesus I Never Knew p.28 describes the birth of Jesus aptly though uncomfortably: “The God who roared, who could order armies and empires like pawns on a chessboard, this God emerged in Palestine as a baby who could not speak or eat solid food or control his bladder, who depended on a teenager for shelter, food and love.”

Isn’t that an amazing description? And yet is is accurate. Why did this happen? Why did the Omnipotent one become so vulnerable? What is the correlation between vulnerability and intimacy? What do you think of the lyrics from the following song called Christ the Lord is Born Today?

God has sent His greatest treasure / Shown His love in greatest measure / Sending Christ to bleed and suffer / Purchasing our joy forever / Let the earth rejoice!