In our understanding, adultery is a matter of ‘pleasure’ between two people, at least one of whom is married. Biblically speaking, adultery was only possible if a man (whether married or not) slept with a married woman. A married man who slept with an unmarried woman was in most cases obliged to assume his responsibilities, i.e. to take her as his wife (for exceptions, see my book or read the Bible carefully). In the case of rape, the man was sentenced to death. As we have seen, a wife (even if she had been a slave until marriage) could obtain a divorce if the husband did not treat her well, whereas according to Jesus, the husband could not divorce a wife unless she had committed an act bordering on adultery. The question was a delicate one, because the legal wording in the Torah is vague, especially as in the case of true adultery, both the woman and the man could theoretically be executed. But in practice, the law was not necessarily applied. The Mosaic law rightly gave rise to debate, especially as God himself had ordered Abraham to listen to the voice of his wife Sarah and divorce Hagar. In this particular case, the divorce was pronounced by God's command for hereditary reasons and not because of adultery.

The problem of adultery is illustrated in the following text (Sirach 23.22-24):
‘Similarly the woman unfaithful to her husband, who provides him with an heir by another man: first, she has disobeyed the Law of the Most High; secondly, she has been false to her husband; and thirdly, she has gone whoring in adultery and conceived children by another man. She will be led before the assembly, an enquiry will be held about her children.’
The text is not concerned with any kind of pleasure, but with descent. In those days there was no contraception. Making love often meant making a baby. It wasn't ‘making a baby’ that was the problem, but ‘taking care of it’. If you're already a parent, you'll have noticed that raising children is expensive. In the context of Matthew 19:9, the Pharisees confront Jesus with the situation where a man would divorce his wife lightly (i.e. without a legally valid reason). In the case of minor marital problems, the biblical solution would have been to marry another woman, not to replace her. Again, if the wife was not treated well, she could ask for a divorce, while the husband could not. ‘And whoever marries her who is divorced commits adultery’ illustrates the problem:  Jesus considered a woman who was divorced lightly to be legally still married. ​We should also note that Jesus is talking about a woman who had been repudiated (against her will), not a woman who had asked for a divorce because her husband had neglected her (sexually, materially or in terms of food).
This contrasts with the law of the Romans, where a woman remained under guardianship all her life, and was divorced by her husband or father. It was under the emperor Augustus that a woman could free herself from guardianship provided she had given birth to at least three children. 
In my book, I will illustrate the problem of divorce and adultery using other revealing texts. There is one verse in particular in the prophet Malachi that is probably even more revealing than the one just quoted. In this case, however, it is a passage that some experts call one of the most difficult verses to translate in the entire Old Testament. Faced with the difficulty of translating it correctly, the translators of our Bibles generally draw more on ecclesiastical thought than on the social problems that led the prophet to write the pericope in question.
In short, we can say that adultery is associated in our understanding with carnal pleasure, whereas in the Bible, it conveys above all a notion of responsibility. 
By Chris Zürcher. Page updated on 24 January 2026