God commanded though Moses: thou shalt not covet thy neighbour’s wife. (Exod 20:17) The Hebrew word for covet means desire. But perhaps a better appreciation of when this desire becomes sinful is gained from the Greek word used by Paul when he repeated the commandment: thou shalt not covet. (Rom 7:7) This word means fix the mind on, or long after. This implies that the mind has been unchecked.
It was exactly this thought that Jesus brought out if He said: whosoever looketh on a woman to lust after her hath committed adultery with her already in his heart. (Matt 5:28) It is not a sin to be tempted, but it is a sin, not to avoid the continuance of that temptation, whether by the eyes or by the mind. Job said: I made a covenant with mine eyes; why then should I think upon a maid? (Job 31:1)
The commandment says not, ‘You shall not covet any woman’, but only, ‘You shall not covet a married woman.’ Jesus said such lust was adultery, not fornication, in the heart.
In biblical times, women married much younger than in Western countries today. And before they were married they were betrothed, and sexual intercourse with a betrothed woman was regarded as adultery. As the type of woman that would induce feelings of lust would almost certainly have been married or betrothed, neither Jesus, nor Job qualify their statement with the words, if she is married. However, when Solomon says: Lust not after her beauty in thine heart (Prov 6:25) he states that the woman is a potential: adulteress. (v 26)
Common sense evaluation of typical situations should lead to the conclusion that if we regard all lust for an unmarried woman as the sin of covetousness, we are adding to the word of God. If a man desires to marry an unmarried woman, he would normally desire her spiritually, emotionally and sexually. Whether or not she marries him, it is perfectly natural and normal for him to lust after her. Paul does not condemn such lust, but rather directs it, when he says: it is better to marry than to burn. (1 Cor 7:9)
In Old Testament times, men were allowed to have concubines in addition to their wife or wives. Although this is no longer allowed, yet, in the light of this, to condemn watching an unmarried belly dancer seems too severe a judgement. But this is the logical conclusion if we say that lusting for any unmarried woman is equivalent to coveting your neighbour’s wife.
However, I do not believe that Jesus said in the context of adultery: if thy right eye offend thee, pluck it out, and cast it from thee: for it is profitable for thee that one of thy members perish, and not that thy whole body should be cast into hell. (Matt 5:29) These same words were said in Matthew 18:6-10 and Mark 9:42-49, in the context of offending a little one that believes in Christ. Solomon says that the evil watch the just as they plot against them, and this is surely the true context of the eye that offends. It is most unlikely that if Jesus gave a terrible warning to those who might harm his people, he would repeat the same warning and apply it to virtually everybody. So Matthew 5:29,30 seem to have been added in the wrong place in the bible, by those who did not understand their true meaning.
This is entirely possible because copyists of the New Testament often did not have the same respect for the Scriptures as did the Jews, often adding notes which later copyists might think were part of the Scriptures. It may be that those who misplaced these words in the wrong context were gnostics, who thought that the body was evil.
And I think that I can prove that they added words to the same gospel by looking at a different chapter with a similar focus. Firstly what does the word of God in Genesis says of Adam: it is not good that the man should be alone. But after Jesus teaching against divorce, Peter is reported as saying that if this is the case: it is good not to marry. Jesus then is reported to agree with this saying, but says that not all men have faith to receive or believe it. There is obviously a contradiction between the two testaments. Yet Jesus says: I came not to destroy but to fulfil. And that man should live by every word of God.
The Old Testament is less likely to be altered than the New Testament. Therefore it appears almost certain that Jesus' words have been tampered with. Almost the last words of the bible warn not to tamper with the word of God, but do not say it will not happen. Jesus avouched the Old Testament and when telling the Pharisees of their errors, would surely have corrected errors in the Scriptures as handed down. But the New Testament was not written when Christ ascended, so it must be that alterations must have crept into this record.
Thou shalt not covet thy neighbour’s wife, is one of the Ten Commandments, and none of the Ten Commandments can be consistently ignored without loss of eternal life, although forgiveness is available. I think that this commandment allows lusting after the beauty of a married woman, but disallows the thought of fornicating with her. But it is less serious to lust for a woman on television, than to lust for your neighbour's wife, because merely seeing a woman on TV, will not hinder condusive relations with anyone, as it may with your neighbour and his wife. And Paul says that the purpose of this commandment is to foster love between a man and his neighbour. (But those who lose eternal life through weakness, are not subject to punishment, as are those who are enemies of God's people.)
If we exercise caution to avoid evil thoughts, our goal should then be positive, heeding Paul's exhortation when he writes: seek those things which are above, where Christ sitteth on the right hand of God. Set your affections on things above, not on things on the earth. (Col 3:1,2) And Paul also writes whatsoever things are true, whatsoever things are honest, whatsoever things are just, whatsoever things are pure, whatsoever things are lovely, whatsoever things are of good report; if there be any virtue, and if there be any praise, think on these things. (Phil 4:8) The psalmist also says: Blessed is the man . . . his delight is in the law of the Lord; and in his law doth he meditate day and night. (Psalm 1:1,2)