2. This law they and their fathers had broken. Their worldly profit swayed more with them than God's command or covenant. When their servants had lived seven years with them they understood their business, and how to apply themselves to it, better than they did when they first came to them, and therefore they would then by no means part with them, though God himself by his law had made them free: Your fathers hearkened not to me in this matter (v. 14), so that from the days of their fathers they had been in this trespass; and they thought they might do it because their fathers did it, and their servants had by disuse lost the benefit of the provision God made for them; whereas against an express law, especially against an express law of God, no custom, usage, nor prescription, is to be admitted in plea. For this sin of theirs, and their fathers, God now brought them into servitude, and justly.