Then Phinehas son of Eleazar, the priest, and the leaders returned to Canaan from their meeting with the Reubenites and Gadites in Gilead and reported to the Israelites. They were glad to hear the report and praised God. And they talked no more about going to war against them to devastate the country where the Reubenites and the Gadites lived. And the Reubenites and the Gadites gave the altar this name: A Witness Between Us - that the LORD is God.
John Calvin
... This is to be carefully observed; for we are able to infer from it that we never revolt from God, or fall off to impiety unless he abandon us, and give us up when thus abandoned to a reprobate mind. All idolatry, therefore, shows that God has previously been alienated, and is about to punish us by inflicting judicial blindness. Meanwhile, we must hold that we persevere in piety only in so far as God is present to sustain us by his hand, and confirm us in perseverance by the agency of his Spirit. Phinehas and the ambassadors speak as if they had been delivered by the children of Reuben, Gad and Manasseh, because there was no longer any ground to fear the divine vengeance, when all suspicion of criminality had been removed. At last similar equity and humanity are displayed by the whole people, when accepting the defence of their brethren they gave thanks to God for having kept his people free from criminality.
Though they had been suddenly inflamed, they depart with calm minds. In like manner the two tribes and the half tribe carefully exert themselves to perform their duty by giving a name to the altar, which, by explaining its proper use, might draw off the people from all superstition.
