Mark 10:5
Ver. 5. And Jesus answered and said unto them,.... With respect to this command, or sufferance of Moses, which they urged:
for the hardness of your heart he wrote you this precept; it was, not because it was right in its own nature, or according to the original will of God; but, because the Jews were such cruel, and hard hearted men, that if this had not been permitted, some of them, that had wives not so agreeable to them, would have used them in a very inhuman manner, if not murdered them; and therefore to prevent further, and greater mischief, Moses indulged them with such a precept; See Gill on "Mt 19:8".