Victorious Conquest: Joshua 3-4
The account of Israel’s victories over two cities, in chapters 2–8, divides into three parts: the city of Jericho in 2:1–6:27, the city of Ai in 7:1–8:29, and a closing covenant renewal in 8:30-35. Israel’s victories over two cities highlighted God’s supernatural power. This theme appears repeatedly in the chapters leading up to the fall of Jericho. In the first episode involving Joshua’s spies and Rahab, Rahab acknowledged in 2:9 that, “The fear of [Israel] has fallen upon us.” And in 2:24, the spies confirmed that, “all the inhabitants of the land melt away [in fear] because of us.” Passages such as Deuteronomy 11:22-25 indicate that God often displayed supernatural power against Israel’s enemies by striking fear into their hearts. Beyond this, when crossing the Jordan, God declared to Joshua, in 3:7, “I will be with you.” This expression indicates that God was fighting with supernatural power for Israel. In 3:10, Joshua declared God’s words to the Israelites, saying again, “The living God is among” — or with — “you.”
Throughout these chapters, our author used Joshua’s initial victories over two cities to point out that his original audience could not win their battles in human strength. Victory came only through the supernatural power of God. Israel's victories over two cities also highlighted that obedience to the standard of Moses' law was necessary for Israel to have victory in battle. The account of crossing the Jordan, in 4:10 tells us that the priests led Israel "according to all that Moses had commanded." Joshua 4:12 reports that the tribes also arranged themselves "as Moses had told them."
Israel's victories over two cities emphasized the importance of the participation of all Israel in the conquest. In the episode of Israel's crossing the Jordan, 3:1, 17 tell us that all the Israelites crossed with Joshua. In 4:14, "The Lord exalted Joshua in the sight of all Israel." And of course, the "twelve men" in 4:4 and the "twelve stones" in 4:8, 9 and 20 represented the twelve tribes of Israel.
How could a loving God command Joshua to completely destroy the inhabitants of Canaan?
In Joshua, God commands the destruction of the Canaanites, not because it's the ideal. The ideal is love your enemies and win them to Christ, but obviously that wasn't an option available in the time of Joshua. If they didn't destroy their enemies, they were going to be infiltrated by pagan customs — for example, the killing of babies who were then often sacrificed and buried in urns and so on. We've found the remains of where Canaanites have done that. Also, anything less than total war would not have eliminated them, which is what we see happening. They didn't have total war, they didn't eliminate them, the Canaanites didn't flee, and so those influences did infiltrate Israel… In Genesis 15, God said that this wouldn't happen, the conquest of Canaan wouldn't happen, until the Amorites had become wicked enough for it to happen. At this point it's kind of like a corporate capital punishment that God is executing on this society. [Dr. Craig S. Keener]