Nontheists will typically counter the moral argument with a dilemma: Is something good because God wills it, or does God will something because it is good? The first alternative makes good and evil arbitrary, whereas the second makes the good independent of God. Fortunately, the dilemma is a false one. Theists have traditionally taken a third alternative: God wills something because he is good. That is to say, what Plato called “the Good” is the moral nature of God himself. God is by nature loving, kind, impartial, and so on. He is the paradigm of goodness. Therefore, the good is not independent of God.
— William Lane Craig, from God Is Not Dead Yet, http://www.christianitytoday.com/ct/2008/july/13.22.html