“It was said, ‘WHOEVER SENDS HIS WIFE AWAY, LET HIM GIVE HER A CERTIFICATE OF DIVORCE’; but I say to you that everyone who divorces his wife, except for the reason of unchastity, makes her commit adultery; and whoever marries a divorced woman commits adultery”. (Matthew 5:31-32)

The rabbis had taken liberty with what Scripture actually said. They referred to Deuteronomy 24:1–4 as if it were given merely to regulate the paperwork when one sought divorce. Thus, they had wrongly concluded that men could divorce their wives for anything that displeased them, as long as they gave “a certificate of divorce.” But Moses provided this as a concession to protect the woman who was divorced not to justify or legalize divorce under all circumstances.

John MacArthur commentary on Matthew 5:31

They said, “Moses permitted a man TO WRITE A CERTIFICATE OF DIVORCE AND SEND her AWAY.” (Mark 10:4)

The Mosaic law, as the Pharisees were forced to concede, nowhere commanded divorce. The passage in question, Deut. 24:1–4, recognized the reality of divorce and sought to protect the wife’s rights and reputation and also regulated remarriage. certificate of divorce. In this document, the husband was required to state the reason for the divorce, thus protecting the wife’s reputation (if she were, in fact, innocent of wrongdoing). It also served as her formal release from the marriage, and affirmed her right to remarry (assuming she was not guilty of immorality). The liberal wing of the Pharisees had misconstrued Deut. 24 to be teaching that divorce was “permitted” for any cause whatsoever (citing as legitimate grounds such trivial events as the wife’s ruining dinner or the husband’s simply finding a more desirable woman), providing the proper legal paperwork was done. They thus magnified a detail, mentioned merely in passing, into the main emphasis of the passage.

John MacArthur commentary on Mark 10:4