Living Christmas trees have caught on in recent years. As opposed to cut trees, these trees are sold in containers of soil and intended for replanting after its use as a Christmas tree. They usually usually include such varieties as Spruce, Pines and Firs. Hey, but what about ... an oak? Okay, chances are good that you may not think about an oak tree when we think of Christmas, but Isaiah uses this interesting image to describe the wonderful salvation that God has given to us.