This verse is to be joined with Deuteronomy 19:3, as is evident, the 4th and 5th verses coming in as a parenthesis, which is usual in Scripture and other authors. And slay him; which is supposed, but not allowed, as appears from the following words. But the avenger of blood is not to be punished with death for killing the manslayer, in case he found him without the borders of the city of refuge after he had been received there, Numbers 35:26,27, because then he was guilty of a new crime, to wit, a contempt of God's ordinance, and a gross neglect of the duty of self-preservation, and therefore deserved death from God, who might permit it to be inflicted by the avenger of blood.
Related Commentaries of Deuteronomy 19:6
Deuteronomy 19:6
6 Lest the avenger of the blood pursue the slayer, while his heart is hot, and overtake him, because the way is long, and slayc him; whereas he was not worthy of death, inasmuch as he hated him not in time past.