John Gill's Bible Commentary Ver. 7. Wherefore I command thee, saying, thou shalt separate three cities for thee .] This was to be done immediately, as soon as they were settled in the land of Canaan, and established in the possession of it, the inhabitants being cut off, or driven out, or however subdued.
Matthew Henry Commentary
Verses 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 refug should be a protection, so that a man should not die for that as crime, which was not his willing act. In Christ, the Lord ou 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 his in their sins.
Original Hebrew על5921 כן3651 אנכי595 מצוך6680 לאמר559 שׁלשׁ7969 ערים5892 תבדיל׃914