If ethics is the study of the life we should live (the good life), then religious ethics is the study of the life God wants us to live. For Christians, gaining clarity on this subject is fraught with difficulty.
One problem is what you might call the “rule-orientation” problem. Ethical systems commonly offer a set of rules for how to live the good life. But Christianity is not a set of rules. In fact, for those who love rules, the New Testament is infuriatingly unhelpful. And even if someone comes to the Bible with the idea of trying to find a compendium of rules, Jesus Himself seems to violate them as often as He upholds them. After all, the rule-oriented leaders of His day were the ones who found Him the most intolerable. His art was far too innovative for their fastidious conventionality.
Another problem is what you might call the “objective ethics” problem. As is natural to think, if God defines the good life and God is fair, then we might expect the good life to be the same for everyone. Although there are certainly some areas of what would ordinarily pass for objective principles, the New Testament again clearly denounces this error under the general principle of Christian liberty. Things that are wrong for one man are good for another and vice versa. And even the thing which might be generally right for one can become wrong in a situation where it alienates people from him or impedes evangelizing or fellowshipping with them. So even when general rules seem to appear, they must always be footnoted by the context and conscience of the individual believer. This again showed itself in the life of Christ and His followers.
But if there is yet a third and truly massive problem plaguing the study of the Christian good life historically, it must surely be the “good enough” problem. This beguiling error tends to think of all possible actions as being either prohibited, permissible, or virtuous. People often think, for instance, that stealing is prohibited, spending money after you have tithed any way you like is permitted, and giving more or all of your money away to charity is virtuous. Unfortunately, the New Testament never gives us ground to hold onto this error. Instead, it says we are to “be perfect.” What this means is that the Christian life is not a matter of avoiding being bad. Instead, virtue, valor, and moral excellence are obligatory. Another way to say this is that there really are no moral options in Christianity. Doing precisely what God wants at any moment is what it means to be good, and everything else is sin. The only life worth living is the perfect one. This is obvious if we merely consider that loving God fully is our basic obligation, which should inspire perfect obedience all the time. Jesus was sinless not because He did “enough,” but because He literally did every single thing precisely right. But considering the first two errors, the perfect life is going to differ greatly from person to person and context to context.
Add to all these difficulties the basic Christian idea that none of us on our own ability can ever actually accomplish God’s perfect will, even if we were insightful enough to see what it was supposed to be in any situation. This means that not only do we need the Holy Spirit moment by moment for guidance, but we need Him to empower us as well.
What, then is Christian ethics? At its simplest, it is the study of knowing the will of the Father at every moment and obeying it by the power of the Holy Spirit enabled in us by the love and sacrifice of our lord Jesus Christ. And once you add all those other wrinkles, it should become clear that Christian ethics is much more like a kind of artistic performance in which something may look quite wrong and be quite right whereas other things may look quite right but be thoroughly wrong. And if we accomplish this, we have merely done what we should.
If this seems to have muddied the waters for you but in a way you don’t really mind too much, then you’re starting to shed some of your pre-Christian ethical misconceptions. And if it also seems to have made things simultaneously far more clear to you, that’s probably because I’m only putting words to the experience of God you’ve already begun to have in your life.