John Wesley on Deuteronomy 19:9

If thou shalt keep all these commandments - But the Jewish writers themselves own, that the condition not being performed, the promise of enlarging their coast was not fulfilled, so that there was no need for three more cities of refuge. Yet the holy, blessed God, say they, did not command it in vain, for in the day's of Messiah the Prince, they shall be added. They expect it in the letter: but we know, it has in Christ its spiritual accomplishment. For the borders of the Gospel - Israel are inlarged according to the promise: and in the Lord our righteousness, refuge is provided for all that by faith fly to him.