The green of the ivy is what it is (symbolic of life? renewal?), but the symbolism of the red of the holly berries should be obvious:
The holly bears a berry,The song touches on various aspects of holly--its blossoms, its berries, its thorns--and relates each of them to the birth of the Savior. And then with each chorus, we go back to the world of plants and greenery.
As red as any blood,
And Mary bore sweet Jesus Christ
For to do us sinners good.
The rising of the sunIt's an interesting juxtaposition, to me at least, of a sacred topic and one that isn't. But then, I guess that's what Christmas ends up being much of the time. We have to switch back and forth between celebrating the birth of the Savior and the gift-giving and light-hanging of the season. There's nothing wrong with that, of course; we aren't asked to spend every moment of our lives in deep, soulful contemplation of the divine. We do other things with our lives, too, and that's normal. So, too, I guess, do we sing about the Savior and ivy.
And the running of the deer,
The playing of the merry organ,
Sweet singing in the choir.
Previously in this series
Do You Hear What I Hear?
I Saw Three Ships
We Three Kings
Bring a Torch, Jeanette, Isabella
In the Bleak Midwinter
Little Drummer Boy