4 And this is the reason why Joshua did so: all the males of the people who came out of Egypt, all the fighting-men, had been overtaken by death in the waste land on the way, after they came out of Egypt. 5 All the people who came out had undergone circumcision; but all the people whose birth had taken place in the waste land on their journey from Egypt had not. 6 For the children of Israel were wandering in the waste land for forty years, till all the nation, that is, all the fighting-men, who had come out of Egypt, were dead, because they did not give ear to the voice of the Lord: to whom the Lord said, with an oath, that he would not let them see the land which the Lord had given his word to their fathers to give us, a land flowing with milk and honey. 7 And their children, who came up in their place, now underwent circumcision by the hands of Joshua, not having had it before: for there had been no circumcision on the journey.
Matthew Henry's Commentary on Joshua 5:4-7
Commentary on Joshua 5:1-9
(Read Joshua 5:1-9)
How dreadful is their case, who see the wrath of God advancing towards them, without being able to turn it aside, or escape it! Such will be the horrible situation of the wicked; nor can words express the anguish of their feelings, or the greatness of their terror. Oh that they would now take warning, and before it be too late, flee for refuge to lay hold upon that hope set before them in the gospel! God impressed these fears on the Canaanites, and dispirited them. This gave a short rest to the Israelites, and circumcision rolled away the reproach of Egypt. They were hereby owned to be the free-born children of God, having the seal of the covenant. When God glorifies himself in perfecting the salvation of his people, he not only silences all enemies, but rolls back their reproaches upon themselves.