R.C.H. Lenski, on the topic of Jesus’ teaching on divorce in Matthew 5:31-32, has this to say:

Jesus does not legislate. (Commentary on Matthew, p.233)

This is such a gem of a quote because so many people look at Jesus as just another religious teacher with his own brand, his own proprietary blend of teachings that he’s hawking. Or they regard Him as the second Moses, another lawgiver whose law supersedes that of Moses, because He is greater than Moses. Moses was just a man and God’s servant, whereas Christ is the Son of God, so what He teaches must of necessity be even more weighty and important. This is what the Roman Catholic church teaches (as far as I can tell), and it’s actually a twisting of passages like Hebrews 3:3-6. Christ didn’t come to load us down with the crushing weight of a law we can’t keep, even more than Moses was able to. He came to fulfill the law in our place, to console us and heal us by the forgiveness of our sins, and to raise us up to live a new and holy life where we delight in God’s law in our inner man. Jesus doesn’t legislate — He delivers from sin, death, and the devil, and opens the gates of heaven to all believers. We err gravely when we give people the impression that Jesus gave us more rules to follow, instead of coming first and foremost to be our Savior and Redeemer from the curse of sin and the law. Lenski is entirely correct — Jesus doesn’t legislate, He saves.