Moses
Deuteronomy 19:1ESV·traditional attribution

“When the LORD your God cuts off the nations whose land the LORD your God is giving you, and you dispossess them and dwell in their cities and in their houses,

John Calvin Reformed @genevareformer

1. When the Lord thy God hath cut off the nations. Moses repeats the same precepts which we have just been considering, that, in regard to murders, the people should distinguish between inadvertency and crime. With this view, he assigns six cities, wherein those who have proved their innocence before the judges should rest in peace and concealment.

Matthew Henry Presbyterian @wholebiblehenry

It was one of the precepts given to the sons of Noah that whoso sheddeth man's blood by man shall his blood be shed, that is, by the avenger of blood, Gen 9:6. Now here we have the law settled between blood and blood, between the blood of the murdered and the blood of the murderer, and effectual provision made, I.

Commenting on Deuteronomy 19:1-13

John Gill Reformed Baptist @doctorgill

When the Lord thy God hath cut off the nations whose land the Lord thy God giveth thee,.... The seven nations of the land of Canaan, whose destruction was of the Lord for their sins, and whose land was a gift of him that had a right to dispose of it to the children of Israel; see Deu 12:29.