Concerning Israel preforming genocide on the inhabitants of Canaan per God’s explicit instructions we would note that the total destruction of the inhabitants of the land is criminal only if the Deity who calls for such a measure is not worthy of all honor. If God’s worth is not so great that those who reject him have committed a crime that cries out for thorough and infinite justice, then the zero-tolerance policy against the people of the land is nothing but a brutal, unjust, and egomaniacal atrocity.
But God’s majestic character is not like the character of mere men whose character could never warrant the wholesale righteous slaughter of their opponents. The ban on the wicked Canaanites heralds the infinite majesty of the justice of God, whose holiness demands perfect loyalty of all creation, and whose worth is such that anything but absolute allegiance is worthy of immediate temporal and eternal death. The conquest of Canaan enacts the Glory of God’s justice against those who look to vain and worthless things to be for them what only God can be for them, and who in the looking to vain and worthless things attempt to de-throne God and enthrone themselves as God. The conquest and genocide of Canaan also displays God’s mercy inasmuch as God allowed them many generations of life despite their rebellion against His majesty. Also, the conquest revealed God’s mercy because in cleansing the land He was rescuing His people from the deleterious effects that the Canaanite putridness would have had on Israel.
And “no,” that supposedly evil God of the Old Testament Canaanite slaughter did not become a user friendly God in the New Testament. In point of fact the New Testament reveals God’s wrath with far more intensity than the Old Testament does. In the Old Testament God never poured His wrath out on the innocent and the righteous as He does in the New Testament.
What does the Canaanite genocide teach us then?
1.) It teaches us that those who sin against God deserve the greatest punishment because the greater the majesty against whom crime is committed the greater the punishment is exacted for the crime. God, having the greatest majesty and glory visits sustained rebellion and conspiracy against His majesty with exacting punishment.
2.) The genocide of the Canaanites is a picture of God’s intent to eternally destroy all His enemies who refuse to turn from their rebellion. The Canaanites did not Kiss the Son, so they perished in the way.
3.) The genocide of the Canaanites teaches us to repent for if God dealt with men of old who did not have the light of revelation we have, how much greater will His dealings be with a generation who has had the revelation of His light for hundreds of years.
However, there is good news in all this. God is patient and long-suffering. Just as he provided time for the Canaanites to fill their cup of wickedness so He provides time for man today to repent. Further, God has provided an ark from His just wrath and He commands all men everywhere to repent and so enter the Ark who is the Lord Christ & His Church to find not only safety but God’s good pleasure.