In case you were wondering: None of this is illegal. It may “raise questions,” but record profits have a way of answering those questions for many people.

No, there is only one thing keeping firms like Goldman Sachs from selling something while at the same time betting against it. That one thing is moral restraint.

Unfortunately, that is exactly what’s missing in our morally relativistic culture. Without a belief in moral absolutes, the only real basis for investor confidence is regulation and other legal coercion. And the sub-prime crisis will lead to much more regulation.

The problem is that regulations often interfere with the efficient operation of markets. For instance, reforms passed in the wake of the Enron scandal had the unintended effect of driving lucrative public offering business overseas.

So you see, free markets—and capitalism itself—can thrive only when corporations and individuals exercise moral restraint. When those restraints fail, government regulation is sure to follow, which in turn makes free markets less free.

Of course, moral restraint requires a set of morals, beliefs that some things are wrong, regardless of what the law says—or, put more simply, the biblical worldview. Otherwise, who can trust people to do what is right when they can make a killing by doing what is wrong? That’s a lesson that Goldman’s clients and millions of homeowners have learned the hard way.