Adultery: A Sin of the Heart

Introduction

The Sin of Adultery

Adultery in the ancient world was specifically the sexual unfaithfulness of a married woman or a man with a married woman. It was seen universally as a sin, although in the cultures around Israel it was strictly a social sin against the husband who had been wronged. You’ll notice that my definition only looks at the faithfulness of the woman. This is because marital faithfulness was not expected for men among most ANE people. Polygamy, prostitution, and even sex with unmarried servants and slaves was common. Virginity was prized in a marriable woman, so the men of her family were careful to make sure she did not have relations before marriage and become a prostitute likely as a result. If a man was guilty of sleeping with a married woman, both of them would be punished together according to the will of the husband who had been wronged.

In Scripture, adultery is also punished with death. While the Bible still refers to adultery usually as the defiling of a married woman rather than a blanket act of unfaithfulness, this is because of the world in which the Jews lived. God is speaking on their level, but like polygamy it is clear that unfaithfulness on either spouse’s part was equally wrong. In Genesis 38:12, the author is careful to tell us that Judah sought a temple prostitute (something obviously immoral to us anyway) only after his wife the daughter of Shua died. Judah is only convicted of adultery when he finds out that the prostitute he slept with was his daughter in law, and the text assumes that it would have been adultery anyway if his wife had still been alive.

Paul brings more clarity to the subject in 1 Corinthians 6:14-17

1 Corinthians 6:15–17 ESV

Do you not know that your bodies are members of Christ? Shall I then take the members of Christ and make them members of a prostitute? Never! Or do you not know that he who is joined to a prostitute becomes one body with her? For, as it is written, “The two will become one flesh.” But he who is joined to the Lord becomes one spirit with him.

Here, Paul identifies sleeping with a prostitute as pornea, that is, sexual activity that is forbidden and immoral. In fact, its thought that the greek word pornh, from which we get the word pornography, comes from a word that refers to sex slaves or prostitues, and so may refer specifically to sleeping with a prostitute. It is used in the OT to translate a Hebrew word which means either to prostitute yourself or, when used passively, to be enticed by a prostitute. You see, in the ancient world they didn’t really have the concept of everyone sleeping around. If you were a woman who was sleeping with someone who was not your husband, you were basically considered a prostitute. If you were a man sleeping with an unmarried woman, you were commiting the same sin. This is because the woman’s body belonged to a man, either her father or her husband, and so it was essentially a violation of those figures. For a man to have sex outside of marriage was to violate his own body, which justifies Paul’s Words

1 Corinthians 6:18 ESV

Flee from sexual immorality. Every other sin a person commits is outside the body, but the sexually immoral person sins against his own body.

And a man who sleeps with a woman who is not his wife sins either against her father, to whom he would pay a fee a marry her unconditionally so as not to cause the father loss. If she swas married, the harm was already done and both the man and the woman were killed unless of course the woman had been raped; then only the man was killed.

In our treatment today, we are going to look both as adultery and immorality (prostitution) together, since Jesus seems to categorize them together and

Why is Adultery Sinful?

Prostitution is banned wholesale throughout Scripture, which means all sexual intercourse outside of marriage.

It is a sin against the faithfulness of God. As image bearers, we are obligated to keep covenantal promises in the same way that God does. Since monogomous marriage is inherently a covenant that promises faithfulness, adultery is a complete vandelization of the love of God in us.

It is a sin against individuals, particularily against either the wronged spouse or, in the case of fornication, the woman’s father and family. It is also a mistreatment of any children born of such a union.

It is a sin against society. It is impossible to live in a society where sociel contracts are not trustworthy. Adultery creates an unstable environment often ending in many hurt people and tend society into an increasingly unloving state.

In our text, Jesus takes this clear and obvious prohibition and breaks it down to the heart. Here, he addresses two different manifestations of adultery that go unrecognized.

Lust

everyone who looks at a woman in order to encourage illicit sexual desires have already committed adultery in their heart.

Strong desire, often positive or neutral. Here of a sexual nature.

Not a feeling of sexual attraction, but a nurturing of it.

Not what you see but why you look.

LXX uses this word when describing the 10th commandment in Exodus 20.

It is good to strongly desire what is good and right and pure. God wants us to have good things and he gives us strong desires so that when we recieve them we are thankful and praise him.

Desiring a person with whom that desire is prohibited, or desiring an intimacy that isn’t lawful with a person, and letting that desire fester and grow, catching glances and lost in imaginations, is adultery because in your heart you are a violator of sexual purity.

Jesus does not mean that looking with lust is as serious a crime as committing adultery, at least not in our relationships with other people. But in the eyes of God the guilt is equally adulterous.

Jesus equals the playing field, making adultery equally heinous for men and women.

A word on pornography (graphic displays of immorality)

Graphic nudity isn’t the inherent problem, the human body is a beautiful thing and in the sinless garden of Eden it was no problem. But sinful, insubordinate passions have changed that. It’s possible to have nudity displayed in a way that most wouldn’t find sexual, such as Michaelangelo’s statue of David or a health textbook. In most cases however, it is for sinful purposes. In Jonathan Edward’s day, medical textbooks sometimes were used as pornographic material.

A dark industry that hurts many people.

A dangerous drug that destroys relationships and the brain God gave you.

Heart prostitution. You are uniting your heart to a stranger on a screen.

Divorce

The bill of divorce was a protection for the woman; a capricious husband could not drive her from his home and afterward claim that she was still his wife. He must give her the document that set out her right to marry someone else - Leon Morris

The Blessed Lifestyle of Violent Integrity and Perservering Faithfulness

Violence

Man who cut off arm stuck in a canyon

But this vivid imagery “emphasizes the crucial importance of taking whatever measures are necessary to control natural passions that tend to flare out of control” - Leon Morris quoting Mounce

The high esteem of marriage faithfulness for a Christian

Hebrews 13:4 ESV

Let marriage be held in honor among all, and let the marriage bed be undefiled, for God will judge the sexually immoral and adulterous.

Conclusion

1 Thessalonians 4:1–8 ESV

Finally, then, brothers, we ask and urge you in the Lord Jesus, that as you received from us how you ought to walk and to please God, just as you are doing, that you do so more and more. For you know what instructions we gave you through the Lord Jesus. For this is the will of God, your sanctification: that you abstain from sexual immorality; that each one of you know how to control his own body in holiness and honor, not in the passion of lust like the Gentiles who do not know God; that no one transgress and wrong his brother in this matter, because the Lord is an avenger in all these things, as we told you beforehand and solemnly warned you. For God has not called us for impurity, but in holiness. Therefore whoever disregards this, disregards not man but God, who gives his Holy Spirit to you.