The Sermon on the Mount: Adultery

You Have Heard It Said

Though the quote Jesus presents is straight from the Ten Commandments (Exodus 20:14), he presents it as if it was a traditional saying instead of a commandment of God. The problem is that the quote is presented in isolation from the remainder of the Old Testament. God had warned “Whatever I command you, be careful to observe it; you shall not add to it nor take away from it” (Deuteronomy 12:32). By presenting this command by itself, much of what God had said concerning adultery is missing. Like the prior tradition on murder, presenting this command alone gives emphasis to the physical act of adultery without addressing its underlying cause.

But I Say to You

When does sin take place? At the point of the actual deed or when the deed was conceived? Jesus points out that in Jewish tradition, the emphasis was placed on physical activity. People were condemned when caught in the act of adultery, but leering at a woman was not condemned. Yet sin is conceived in the heart. A person considers and decides to commit a sin before the actual opportunity to sin presents itself (Mark 7:21-23). The thoughts of committing sin is a sin in itself.

For this reason, we need to remove the sources of lustful thoughts from before us. Is it proper for a Christian to idly watch fornication being committed on television, listen to music glorifying an adulterous relation, or read books designed to arouse our passion? Jesus uses hyperbola to emphasize that sin is dangerous enough that we should use extreme measures to avoid it. He is not stating that a person should literally maim themselves, but pointing out that we may need to take steps that might seem extreme to the world (Matthew 18:8-9)– refusing to watch certain shows, or perhaps television altogether, tossing books or music which contain immoral ideas, or avoiding beaches where people are not properly clothed. None of these things are nearly as extreme as plucking out an eye or cutting off a hand, though people in the world will often act as if they were unreasonable steps.

 Old Testament Teachings on Adultery

The Old Testament did not focus solely on physical action, it condemned lustful thoughts as well. “For the commandment is a lamp, and the law a light; reproofs of instruction are the way of life, to keep you from the evil woman, from the flattering tongue of a seductress. Do not lust after her beauty in your heart, nor let her allure you with her eyelids. For by means of a harlot a man is reduced to a crust of bread; and an adulteress will prey upon his precious life. Can a man take fire to his bosom, and his clothes not be burned? Can one walk on hot coals, and his feet not be seared?” (Proverbs 6:23-28). No one can hold lust in his heart and not expect his soul to be burnt. What makes a man a miser is not what he does or says, but what he thinks in his heart (Proverbs 23:7).

That thoughts, or desires, are a factor in sin can be seen in several laws. In Deuteronomy 22:22-27 are a set of laws dealing with rape. When a supposed rape takes place in town, yet no one hears a struggle or outcry, then it is assumed that both the man and woman were having consensual sex; thus, both are condemned to death. But when it appears to have been rape, then only the man is condemned to death, the woman is not considered to have sinned. The action did not determine whether a sin took place on the woman’s part, but the desire within the woman’s heart.

Sins of the heart were condemned in the Old Law, but in dealing with judgment being conducted by men, the law discussed the physical evidence that could be seen by men that would give an indication of the state of the heart. For example, a judge trying to determine whether a death was accidental or intentional was told to look to see if there was evidence of past hatred between the killer and the slain (Numbers 35:15-25).

New Testament Teachings on Adultery

There are no differences between the Old Testament and the New Testament in regards to adultery. The act of adultery is clearly condemned (I Corinthians 6:9; Hebrews 13:4), but we are told that sin starts before we give in to our desires (James 1:13-16).

In speaking of the false teachers who would arise, Peter condemns them for “having eyes full of adultery and that cannot cease from sin” (II Peter 2:14). Continuing Jesus’ teaching, Paul urges Christians to take steps to eliminate temptations from their lives. “Therefore put to death your members which are on the earth: fornication, uncleanness, passion, evil desire, and covetousness, which is idolatry” (Colossians 3:5; see also Galatians 5:24). Sin and the thoughts leading up to sin need to be avoided. (I Thessalonians 5:21-22). Christians are even to take steps to remove things associated with sinful thoughts from their lives (Ephesians 5:3-6).