Some of God’s laws are given as general principles such as, “You shall not steal. You shall not murder.” And then we can apply these general principles in specific situations. We know that it is wrong to steal a particular thing from a specific person because in general it is wrong to steal. However, some of God’s laws are just the opposite. They give a specific example, from which we are supposed to derive the general principle. These are called “case laws.” Let’s look at some examples.
Deuteronomy 22:8 states, “When you build a new house, you shall make a parapet for your roof, so that you will not bring bloodguilt on your house if anyone falls from it.” It was common at the time in that part of the world for houses to have flat roofs upon which members of the household or guests could walk about for recreation, meditation, relaxation, or conversation. God’s law therefore insists that such a roof should have a rail or fence around it, so that people would not accidentally fall. If the home owner failed build a parapet and a guest falls from the roof, then the home owner is held responsible.
The general principle we are supposed to infer from this specific illustration is that we should take reasonable precautions to make our homes safe for family and guests. And if a home owner fails to do so, then he or she is held responsible for injuries or deaths that happen as a consequence. Does this law still apply today? Yes, this is a moral law and thus the principle still applies. Does this law mean that all modern homes must have a fence around their roof? No—only those homes that have a flat roof or deck that is easily accessible to guests. The law really isn’t about roofs and parapets; it is about the preservation of human life.
The specific, detailed requirements of this law (fence around a roof) only apply if the circumstances are the same (you have a flat roof that is easily accessible to guests). But the general principle of taking precautions to make a home safe applies universally. Perhaps a modern illustration of this biblical principle would be to build a safety rail next to a flight of stairs. If a flight of stairs lacks sufficient safety railing, and a guest falls and is injured, the home owner is responsible. The principle given in Deuteronomy 22:8 is easy to understand even when the specific circumstances differ.
Case laws may seem “backwards” to some people. Why does God give us a specific illustration of a general principle, and not simply state the general principle directly? Actually, He does both. The Ten Commandments are given as general principles. But without case laws, we might not always apply the Ten Commandments properly. For example, the Sixth Commandment states, “You shall not murder” (Exodus 20:13). The word “murder” refers to an unlawful killing of a human being. But how are we to decide which kinds of killing are unlawful? For example, is it “murder” to kill an enemy soldier in combat? Is it unlawful to kill in self-defense? Is a person guilty of murder if his accidental actions result in the death of another person? The Sixth Commandment does not (by itself) answer any of these questions. We need the case laws of the Old Testament in order to properly apply the Sixth Commandment.
We learn from the case laws that accidental deaths are not considered murder (Deuteronomy 19:4–6), unless the death resulted from avoidable negligence (Deuteronomy 22:8). Public executions for capital crimes are not considered murder; they are permitted (Deuteronomy 13:6, Leviticus 20:15–16). Killing in combat in a just war is also permitted (Deuteronomy 13:14–15). However, the premeditated killing of an innocent person is murder, and warrants capital punishment (Exodus 21:14, 23:7). So the case laws of the Old Testament are not contrary to the Ten Commandments. Rather, they help us to understand and properly apply the Ten Commandments.
God gives case laws because He knows that the human mind is often able to extrapolate general principles from specific instances more easily than if we had been given the general principles directly. Human beings possess the ability (given to us by God) to learn by example. Case laws help us understand how to apply the general principles given in the Ten Commandments.