It is important to examine whether there is apparent inconsistency regarding the Pharisees' response to Jesus about the permission to issue a certificate of divorce. In Mark, they claim, “Moses permitted it,” while in Matthew, in response to Jesus’ directive grounded in the law—that what God has united, man should not separate—the Pharisees ask about the commandment of Moses, “Why then did Moses command to give a certificate of divorce and send her away?” Jesus responded by rebuking them, stating that Moses permitted divorce due to the hardness of their hearts, indicating that it was not intended that way from the beginning. Mark includes this response directly after the question concerning divorce.
The order or wording in which we receive these accounts does not affect their authenticity. The crucial aspect lies in the dialogue between the Pharisees and the Lord, who prohibited divorce, citing the divine institution of marriage established by God. Whether they referenced the letter of divorce from the same Mosaic law or used that authorization to challenge Jesus’ prohibition, the Lord aimed to clarify why Moses allowed divorce. This intention is reflected in Mark's portrayal. Meanwhile, the Pharisees sought to force Jesus into a contradiction with Moses’ allowance for divorce, which they believed was a fixed point of law, thereby trying to provoke Him into denying it.
Their objective is articulated in Matthew’s account, wherein it is the Pharisees who mention the Mosaic commandment to confront the Lord regarding His disallowance of divorce. The differing intentions of those speaking, along with the purpose behind their words, are made evident by both gospel writers. The distinct narratives employed by each do not lead either away from the truth.
The debate may have unfolded in this manner: Mark starts with Jesus inquiring about the permissibility of divorce by asking the Pharisees, "What did Moses command you?" They claimed that Moses authorized the issuance of a certificate and the subsequent dismissal of a wife. In response, Jesus, as recorded by Matthew, quoted from the very scripture given by Moses, reminding them of God’s original design for marriage: “Have you not read that He who created them from the beginning made them male and female?” The Pharisees then rephrased their initial answer as a question: “What did Moses command to give a certificate of divorce?” Jesus warned them that the reason behind Moses’ allowance was their hard-heartedness. Mark encompasses these admonitions succinctly, even though they serve to refute the Pharisees’ repeated argument, as detailed by Matthew. Nevertheless, this does not undermine the integrity of the account, as Jesus’ precise reply to their claim remains intact, despite the Pharisees reiterating their point.