Consider the following situation: you are in your final semester of college, and one class is borderline. If you pass the final, you pass the class. If you pass the class, you graduate. If you don’t pass the final, your diploma is delayed another semester. Now suppose you’re going into engineering, where you are required to work under a practicing engineer before you’re eligible to become licensed yourself. But this experience (typically 2 to 4 years) doesn’t start counting until your after actual diploma date. A lot is riding on this one exam. Having retaken a class may not matter in 20 years after you’ve established a solid work record, but the stakes are high as you get ready to start your career. Lastly, suppose you have the opportunity to get the exam answers in such a way that you know you won’t get caught and nobody will ever know you cheated. You will benefit greatly, and there will be no foreseeable “casualties” from your actions (i.e. the exam is not graded on a curve, so your cheating will not adversely affect anyone else’s score, and so on). Would you do it?
If your ethical standard is of a consequentialist nature (i.e. all that matters is the consequence, or end result), you could reasonably justify cheating in this case. It benefits you, without harming anyone else, so why not? For instance, if you take atheist Sam Harris’ view of basing our morals on whatever promotes human flourishing, then you could argue that the cheating would certainly appear to help you flourish in your career; and if it doesn’t hurt anyone else, that’s a net gain, right? But I’d like to suggest that the idea of simply not harming others isn’t sufficient for an ethical standard because of unforeseen consequences. We may truly believe that an action of ours, though generally viewed as unacceptable ethically, will be alright in a particular instance because it’s “not hurting anybody.” But we are notoriously short-sighted, especially when it benefits us personally. Whether intentionally or not, we often selectively look at the reasons for and against a course of action, ignoring or minimizing the potential consequences of our desired action if those consequences might stop us from acting. But even if we are seriously, conscientiously weighing the pros and cons of a particular decision fairly, we still have our very finite knowledge hindering us. We simply do not, and cannot, know all possible ramifications of our actions, either immediate or in the distant future. In this case, the cheating may very well contribute to a timely graduation and successful career, with no harm to anyone else. But what we may not see from our limited perspective is that it will actually hurt us in the long run. For one successful lie often sets the stage for others later. At some point, our example student may find himself in another ethical dilemma. But now, ten years later as an engineer, it’s no longer grades riding on his decision, but people’s lives. Again, he might decide he has figured a way out of the dilemma where some unethical behavior won’t matter because “nobody will ever know” and “it won’t hurt anybody”. But, the devil’s in the details, as they say. This time, there is a subtle distinction he missed, and now people have died because of his lie. An investigation may determine the immediate cause of the tragedy, and find him guilty of misconduct or negligence in that particular design, but is that the root of it, or was the deeper cause ten years earlier when he learned that he could get away with cheating? Ideas have consequences, and one of the consequences of consequentialist systems of ethics (like utilitarianism and situation ethics) is a reliance on one’s own limited and fallible knowledge as the standard of right and wrong. This situation was aptly described in the Bible when it says that people in the land “did what was right in their own eyes.”
Instead of relying on our error-prone selves to guess at right and wrong, might I suggest a better standard? It’s hard to judge the sweep in a line without a ruler to put next to it. Ask different people and you’ll likely get different answers. But get out a ruler, and that “official” standard settles it. Only having God as a source of our ethics is sufficient. Recognizing that God is the source of morality eliminates the idea that differences in ethics may simply be differences of culture or time. God is the “third-party” that’s needed to settle these differences. Unforeseen consequences are the bane of utilitarian ethics, but that’s not a problem for an omniscient God. We can rely on His decrees because He is all-knowing. Recognizing that aspect of His nature also eliminates the rationalization that nobody has to know the wrong we do, for God knows. Recognizing that “it is appointed for men to die once and after this comes judgment” reminds us that we will be held accountable for every action, whether anybody happened to be harmed by a particular deed or not. God cares not simply about the results of our actions, but the root of our actions – our motives and intentions. But there is hope in knowing what to do: He has revealed to us what is required of us, both in the natural law written in our hearts, and in the special revelation of the Bible. He has also provided a way for us to made acceptable before Him in spite of our all-too-imperfect humanity: the redemptive sacrifice of His Son, Jesus Christ. And His way is always the right choice.
 Judge 17:6.
 Hebrews 9:27. See also, Ecclesiastes 12:14.
Additional Resources: For an in-depth comparison of different ethical systems with support and objections to each, I recommend Philosophical Foundations for Christian Worldview, Part V: Ethics, by J.P. Moreland and William Lane Craig, (Downers Grove, Intervarsity Press, 2003).