Religious leaders tested Jesus on this. They asked Him if it was lawful for a man to divorce his wife for whatever reason he wanted. They believed they had the Scriptures on their side.
Jesus replied, “Have you not read, that He who created them from the beginning made them male and female, and said, ‘For this cause a man shall leave his father and mother and shall cleave to his wife; and the two shall become one flesh’? Consequently, they are no longer two, but one flesh. What therefore God has joined together let no man separate.” Matt 19
Jesus was not talking specifically to his followers at this point; he said this to unbelievers. Jesus taught them that even when unbelievers marry, God joins them together. Otherwise He would have nothing against them when they divorce. God has something against unbelievers who divorce; they took a beautiful gift and treated it as an inconvenience.
Jesus would have left it there, because there he stated the principle, but the religious leaders didn’t want the principle. They wanted a way out, an escape, “freedom.” They pointed out to Jesus that Moses allowed a man to divorce.
Jesus said, “Because of your hardness of heart, Moses permitted you to divorce your wives; but from the beginning it has not been this way. And I say to you, whoever divorces his wife, except for immorality, and marries another woman commits adultery.”
The disciples said to Jesus, “If the relationship of the man with his wife is like this, it is better not to marry.” A man who does not count the cost would be better off if he never married in the first place. If a man is not serious about commitment, it is better if he never marries, and if he divorces, he incurs a terrible debt.
