When What Ceases to be a Servant Becomes Tyrant

Philip Yancey, in the introduction to G.K. Chesterton's book, Orthodoxy, p. xvi:

The churches I attended had stressed the dangers of pleasure so loudly that I had missed any positive message.  Guided by Chesterton, I came to see sex, money, power, and sensory pleasures as God's gifts which, in a fallen world, must be handled with care, like explosives.  We have lost the untainted innocence of Eden, and now every good things represents risk as well, holding within it the potential for abuse.  Eating becomes gluttony, love becomes lust, and along the way we lose sight of the One who gave us pleasure.  The ancients turned good things into idols; we moderns call them addictions.  In either case, what ceases to be a servant becomes a tyrant.

Or, as Tim Keller would say it, it is turning good things into ultimate things.