יהושע, פרק ה׳, פסוק ז׳

The transition of generations in the desert reaches its practical climax just moments before the Israelites enter the Land of Israel. The older generation that departed from Egypt has passed away, and their children, born during the long years of wandering, now step forward to take their place and inherit the land.

It was God Himself who established this new generation in place of their fathers [רד״ק, ביאור שטיינזלץ]. This reality serves as the direct fulfillment of a divine promise. During the earlier sin of the spies, the older generation expressed fear that their young children would be taken as spoils. Instead, God ensured that these very children would be the ones to survive, enter, and take possession of the promised land [מלבי״ם].

However, this younger generation lacked circumcision, making a mass event necessary before they could continue their journey. The sons remained uncircumcised because their fathers had not performed the ritual during their travels. The unpredictable conditions of the journey and the constant state of wandering provided a valid and justified excuse for delaying this commandment [מלבי״ם].

Because the general population of those who left Egypt had not circumcised their children on the way, there were no circumcised men available and fit to perform the procedure. Consequently, Joshua himself carried out the circumcisions [מצודת דוד]. While this was a mass event for the desert generation, there were notable exceptions. Joshua did not need to circumcise the men of the tribe of Levi, nor the sons born to those righteous individuals who were under twenty years old when the decree of the spies was issued, as these groups were already circumcised [מלבי״ם].