Sproul on Holiness and Idolatry

God-willing, this coming Sunday I'll preach the second message in our series on the gospel. The title of this sermon is, "The Gospel and God's Holiness." In preparation of this sermon I am reading through R.C. Sproul's The Holiness of God. The book has been excellent in many, many ways thus far. I found the following quote about idolatry one example of this fact:

When we call things holy when they are not holy, we commit the sin of idolatry. We give to common things the respect, awe, worship, and adoration that belong only to God. To worship the creature instead of the Creator is the essence of idolatry.