what is adultery according to the bible

"You shall not commit adultery" is the seventh commandment. Adultery is the corruption of the marriage bond, and the prohibition would certainly extend to every kind of such corruption whether persons are married or not. In the New Testament, though the words, "Ye shall not" are not used, yet the evil of fornication is no less warned against (Acts 15:29; 1 Thes.4:3-4). Homosexuality is worse still -- a most flagrant corruption of the bond of marriage (Rom.1:26-27).

This was forbidden in the ten commandments; but neither there nor anywhere else is the sin defined. It seems clear, that as far as the man was concerned, if he had intercourse with a woman unless it was with a married woman, he would not be charged with adultery, though he himself might be married; indeed how could he be when he was allowed more wives than one, as well as concubines and slaves? If he committed adultery with a married woman or with one betrothed, both were to be put to death. Deut. 22:22-24. With the woman it was stricter, she must have no intercourse with any man but her husband. If a man was jealous of his wife there was the ordeal of the bitter waters provided to test her innocence. Num. 5:11-31. But we do not read that any man or woman was stoned for adultery, nor that any woman drank the bitter waters. We know from the New Testament that Moses had, because of the hardness of their hearts, allowed a certain looseness, and a man could divorce his wife for any cause, which was easier than bringing a suspected wife to trial. It may be that the men themselves had not good consciences, like those who brought the adulterous woman to the Lord in John 8:3. We have a dreadful picture of guiltiness in Judges 19: and Jeremiah charges Israel with being "as fed horses in the morning, every one neighed after his neighbour's wife," which loudly called for judgement. Jer. 5:8; Jer. 13:27. The Lord declared that a man morally committed adultery (or fornication) in his heart if he lusted after a woman. Adultery had also a typical meaning. Israel had been espoused to Jehovah, but instead of being a faithful wife she had sought other lovers. "With their idols have they committed adultery." Ezek. 23:37. So the false church, who has Jezebel in her midst, the Lord will cast her "and them that commit adultery with her into great tribulation, except they repent of their deeds." Rev. 2:22.

The whole of Scripture is full of the errors of fornication (Acts 15 v 29) and adultery (Exodus 20 v 14). The first is sexual relationship outside of marriage and the second sexual relationship with a married person. We must clearly state that physical affection is only intended by God for one man and one woman and that within the confines of marriage and to a very limited extent by a couple committed to marriage (see previous chapter).

The Lord Jesus now explains that before God it is not just the accomplished act that is sin, but the looking with lust on a woman, for this is adultery in the heart. The word “adultery” shows that either the man or both are married. Nevertheless, no unmarried believer should think that these words of the Lord have nothing to say to him.

The Lord is not speaking here about accidental, unintentional looks which can hardly be avoided, but about the conscious covetous looking: “Whosoever looketh on a woman to lust after her … ” The intentional look is therefore preceded by the sinful thought in the heart.

The Lord Jesus now explains that before God it is not just the accomplished act that is sin, but the looking with lust on a woman, for this is adultery in the heart. The word "adultery" shows that either the man or both are married. Nevertheless, no unmarried believer should think that these words of the Lord have nothing to say to him.

The Lord is not speaking here about accidental, unintentional looks which can hardly be avoided, but about the conscious covetous looking: "Whosoever looketh on a woman to lust after her..." The intentional look is therefore preceded by the sinful thought in the heart.

But what has become of marriage through sin! It was not the will of God that Lamech, Abraham, Jacob, Solomon and other men of the Old Testament should have several wives at the same time, and this only brought distress into their families. How serious was the adultery David committed with Bathsheba! And how are things today with regard to matrimonial morals — not only in the world, but also among Christians? In recent decades Biblical standards in society have been systematically done away with in this area too.

In God's sight immoral behaviour is so abominable that Paul had to write to Ephesus: “But fornication, and all uncleanness, or covetousness, let it not be once named among you, as becometh saints” (Eph. 5:3). This means that we should not mention these things frivolously and so make little of them. The Bible speaks very clearly as to God's judgment about these sins. Holy Scripture not only calls prostitution fornication, but all extramarital intercourse, even where there may be the intention to get married, and even if it is done only once (cf. Gen. 34 and 38). In the world today the word fornication is only used in connection with the first meaning. In the New Testament, however, extramarital intercourse in general is called fornication, that of married persons is called adultery, and both are condemned as abominable sin (Matt. 15:19; 1 Cor. 6:9; Heb. 13:4).

In the Old Testament, adultery, unfaithfulness towards the spouse for the satisfaction of lust, was to be dealt with most severely. According to the law of Sinai this sin had to be punished with death (Lev. 20:10; Deut. 22:22-24). In the first place the law contained God's regulations for the outward and social life of His earthly people, and for this reason only the accomplished offence was to be punished, even though the tenth commandment forbad the coveting of the neighbour's wife (as well as all his possessions. Ex. 20:17). If a Jew kept the commandment not to commit adultery, he was acting according to God's will and contributed towards the maintenance of the people's community according to God's order. Fear of the punishment threatened certainly contributed to this. However, the mere outward observance of this and all the other commandments could not justify him before God.

But what has become of marriage through sin! It was not the will of God that Lamech, Abraham, Jacob, Solomon and other men of the Old Testament should have several wives at the same time, and this only brought distress into their families. How serious was the adultery David committed with Bathsheba! And how are things today with regard to matrimonial morals-not only in the world, but also among Christians? In recent decades Biblical standards in society have been systematically done away with in this area too.

In God's sight immoral behaviour is so abominable that Paul had to write to Ephesus: "But fornication, and all uncleanness, or covetousness, let it not be once named among you, as becometh saints" (Eph. 5: 3). This means that we should not mention these things frivolously and so make little of them. The Bible speaks very clearly as to God's judgment about these sins. Holy Scripture not only calls prostitution fornication, but all extramarital intercourse, even where there may be the intention to get married, and even if it is done only once (cf. Gen. 34 and 38). In the world today the word fornication is only used in connection with the first meaning. In the New Testament, however, extramarital intercourse in general is called fornication, that of married persons is called adultery, and both are condemned as abominable sin (Matt. 15: 19; 1 Cor. 6: 9; Heb. 13: 4).

In the Old Testament, adultery, unfaithfulness towards the spouse for the satisfaction of lust, was to be dealt with most severely. According to the law of Sinai this sin had to be punished with death (Lev. 20: 10; Deut. 22: 22-24). In the first place the law contained God's regulations for the outward and social life of His earthly people, and for this reason only the accomplished offence was to be punished, even though the tenth commandment forbad the coveting of the neighbour's wife (as well as all his possessions. Ex. 20: 17). If a Jew kept the commandment not to commit adultery, he was acting according to God's will and contributed towards the maintenance of the people's community according to God's order. Fear of the punishment threatened certainly contributed to this. However, the mere outward observance of this and all the other commandments could not justify him before God.

For that reason the Lord now says, “But I say unto you, That whosoever looketh on a woman to lust after her, hath committed adultery with her already in his heart” (v. 28). Because of the teaching of the scribes and Pharisees, the Jews thought the mere outward observance of the law was the way to be justified before God. Here, the Lord points to the human heart and shows that adultery has its source there. This is not a “spiritualisation of the law,” as is sometimes said. He reveals for the first time something which had to become clear by experience to every honest Israelite, namely, that everyone who endeavoured to keep the commandment, “Thou shalt not commit adultery,” had within themselves those very lusts which led to the actions forbidden by God, and had not the strength to overcome them. The lusts were even provoked by the commandment: “ … for I had not known lust, except the law had said, Thou shalt not covet” (Rom. 7:7-11).

In His own authority the Lord Jesus contrasts the commandment, "Thou shalt not commit adultery," with His words, "But I say unto you." He does not speak against an interpretation which is more favourable to man and a weakening of the divine commandment, (unlike verse 22), and certainly not against the commandment itself, for He was not come to destroy but to fulfil.

For that reason the Lord now says, "But I say unto you, That whosoever looketh on a woman to lust after her, hath committed adultery with her already in his heart" (v. 28). Because of the teaching of the scribes and Pharisees, the Jews thought the mere outward observance of the law was the way to be justified before God. Here, the Lord points to the human heart and shows that adultery has its source there. This is not a "spiritualisation of the law," as is sometimes said. He reveals for the first time something which had to become clear by experience to every honest Israelite, namely, that everyone who endeavoured to keep the commandment, "Thou shalt not commit adultery," had within themselves those very lusts which led to the actions forbidden by God, and had not the strength to overcome them. The lusts were even provoked by the commandment: "... for I had not known lust, except the law had said, Thou shalt not covet" (Rom. 7: 7-11).

Let one instance suffice out of the seven occasions in that discourse when our Lord said, “I say to you.” “Ye have heard that it was said of them of old time, Thou shalt not commit adultery: but I say to you, That whosoever looks on a woman to lust after her has committed adultery with her already in his heart” (Matt. 5:27-28). Where is there the setting aside of the law? Nay, He upheld it. The law was content to forbid the actual act, the Lord went further, and not only forbad the outward act, but the inward desire.