Ethics vs. Faith

I've always considered myself an ethical person, but what is "ethics"? One definition dictionary.com provides is "that branch of philosophy dealing with values relating to human conduct, with respect to the rightness and wrongness of certain actions and to the goodness and badness of the motives and ends of such actions." But what determines "goodness" and "badness"?

For many people, the belief in a higher power and an afterlife are what are at the bottom of ethical beliefs. They act in a way that will allow them to be in the good graces of that higher power. This is clearly illustrated in the book of psalms. A good number of the psalms speak of God protecting those who believe in Him and smiting those who don't. The thing that seems unclear to me is whether this is a display of ethics or a display of spiritual faith.

Clearly, ethics play a part in the book of psalms. However, the reason people reading the psalms feel the need to act in an ethical manner is because of their deep faith in God. Because they have faith that God will protect them as long as they act ethically. So the answer, I think, is not that the psalms are more about ethics or more about spiritual faith, but rather that they are equally about both aspects because both go hand in hand.