Peace on Earth? (Luke 2:14)

We all long for a world of peace; yet no matter how much we long for it, peace never seems to be achieved. Is peace even possible? Or is it just a nice sentiment for Christmastime? The heavenly hosts want us to understand their announcement: peace on earth is not a result of earth achieving the status of heaven, but rather heaven coming to earth. So where does true peace come from? What does true peace look like in action? And how should we respond to true peace among us?