Mark 10:4
They said, Moses permitted a man to write a certificate of divorce and send her away — the Pharisees accurately identify the Mosaic permission but call it a command (in Jesus' question) versus a permission (in their answer). The certificate of divorce (Deuteronomy 24:1) was intended to protect the divorced woman by providing documentary evidence of her freed status, allowing her to remarry. The Pharisees present the permission as the standard; Jesus will go behind the permission to the creation design.