The battles that the Jews fought in Joshua are types of some mop-up battles that saved Jews will fight after the battle of Armageddon. They will begin when, at the “end” of Antichrist’s career, tidings out of the east and north will trouble him (Dan.11:44,45). The tidings out of the north will come from Babylon, where he will hear that the 10 kings who had earlier aligned themselves with him have burned his church and religious system, Babylon the Great (Rev.17: 12,16). The tidings out of the east will be the troubling news he’ll hear that an angel dried up a river to open the path for some armies to reach him at Armageddon (Rev.16:12-16).
One of those kings will likely be the king of Syria. The beast himself will be an Assyrian (Ezek.31:3-9), so news that the Jews in his home country have turned on him will trouble him greatly. The other king will likely be the king of Egypt. Egypt is not east of Israel where the beast will be sitting in the temple at that time, but God will let the beast conquer Egypt (Isa.19:4; Dan.11:42) to make them believe on Him, and it will work (Isa.19:18-22). Then Egypt will team up with Syria (v.23) to launch a counterattack against the beast.
So the battles that the Jews wage here in Joshua will be types of the mop-up battles that saved Jews in Egypt and Syria will wage after Armageddon. The Rock of Ages will break the kingdoms of men to pieces at Armageddon (Dan.2:34,35), but “the wind” will blow them away afterward, and Isaiah identifies the wind as “men of Israel” (Isa.41:14-16). These battles in Joshua seem to take 75 days, the same amount of time the future mop-up battles will take (Dan.12:12).
The battle the Jews lost at Ai will be mirrored in the future when some Jew who isn’t a true Jew, i.e., a saved Jew (Rev. 2:9;3:9) will bring idolatry into the camp of future Israel and curse them to lose a battle. But he’ll be caught and eliminated the way Achan was, and the Jews will win the rematch.
The Jews burned Ai as God commanded (Josh.8:8cf.Deut. 13:12-16). The people were slain to help exterminate that demonic race of giants, but the king was singled out for a slower, less merciful punishment (Joshua 8:23,27-29) be-cause the leaders of a nation are more culpable for the idola-try found in a nation. This is a type of how the hottest places in hell are not reserved for Hitler or serial killers, who can only take physical life, but for the leaders of false religion, who rob men of eternal life.
Abraham built an altar when God gave him the Promised Land (Gen.12:7,8), and Joshua built another one on the same spot to reclaim it (Josh.8:30). The altar was built with uncarved stones (v.31) as God commanded (Ex.20:25). This symbolized how the work of men’s hands pollutes the blood on the altar, just as human works pollute Christ’s sacrifice.
Joshua wrote the law of Moses on the stones of the altar (Josh.8:32), just as God commanded (Deut.27:1-5). Deuteronomy 27:9-13 instructed Joshua to put 6 of Israel’s tribal leaders on one mountain outside Ai, and 6 on the other, which Joshua interpreted to mean with their people (Josh.9:33). “Ebal” cursed, because the name means stone mountain, and represented the stone tablets of the law God gave Moses on the mountain that cursed the Jews because they couldn’t keep it. But “Gerizim” blessed, because that name means a cutting off. Add it all up, and it explains how saved Jews will be able to enter the kingdom. They’ll have to keep the law to enter it, just as the Jews in Joshua had to pass between the blessings and cursings of the law to enter the Promised Land. But if their foreskins are cut off, then God will be able to circumcise their hearts (Deut.30:6) by the cutting off of Christ from the land of the living (Isa.53:8).
The reading of every word of the law (Josh.8:34,35) would have taken 14 hours, but it shows the respect they had for the Word of God through Moses—the same respect we should have for the Word of God to us through the apostle Paul!