Joshua 5:2

1 Now when all the Amorite kings west of the Jordan and all the Canaanite kings along the coast heard how the LORD had dried up the waters of the Jordan before the Israelites until they had crossed over, their hearts melted and their spirits failed for fear of the Israelites.

2 At that time the LORD said to Joshua, “Make flint knives and circumcise the sons of Israel once again.”

3 So Joshua made flint knives and circumcised the sons of Israel at Gibeath-haaraloth.

4 Now this is why Joshua circumcised them: All those who came out of Egypt—all the men of war—had died on the journey in the wilderness after they had left Egypt.

5 Though all who had come out were circumcised, none of those born in the wilderness on the journey from Egypt had been circumcised.

6 For the Israelites had wandered in the wilderness forty years, until all the nation’s men of war who had come out of Egypt had died, since they did not obey the LORD. So the LORD vowed never to let them see the land He had sworn to their fathers to give us, a land flowing with milk and honey.

Read all of Joshua 5