9 because you are diligently living the way I'm commanding you today, namely, to love God, your God, and do what he tells you all your life; and when that happens, then add three more to these three cities

Matthew Henry's Commentary on Deuteronomy 19:9

Commentary on Deuteronomy 19:1-13

(Read Deuteronomy 19:1-13)

Here is the law settled between the blood of the murdered, and the blood of the murderer; provision is made, that the cities of refuge should be a protection, so that a man should not die for that as a crime, which was not his willing act. In Christ, the Lord our Righteousness, refuge is provided for those who by faith flee unto him. But there is no refuge in Jesus Christ for presumptuous sinners, who go on still in their trespasses. Those who flee to Christ from their sins, shall be safe in him, but not those who expect to be sheltered by him in their sins.