Why does the Old Testament command conquest and permit slavery?

A man hears two charges, and they are not the same charge. One is that God told Israel to destroy Canaan. The other is that the Law talks about slaves. If you answer both with ‘that was a long time ago,’ you have not answered either.

Canaan sits inside a story the Bible tells on itself. Genesis 15:16 says the iniquity of the Amorites was not yet complete — a delay measured in centuries, not a sudden ethnic mood. The command is judicial, aimed at particular cities and practices, not a general order to clear the map. Rahab and her house are spared because the door was open to faith. That is not how a race war works. Ancient war writing is also full of total language that the same books then undercut with survivors and later coexistence. Read the whole narrative before you preach a slogan from one verse.

Slavery in the Torah is mostly debt and household service in a world without bankruptcy courts, with release in the seventh year for the Hebrew servant and protections a chattel code does not bother to write. Kidnapping a person to sell him is a capital crime (Exodus 21:16). The foreign slave laws are still harsh, and the Christian does not pretty them up into modern HR. They are a brake on an ancient economy, not the last word. The last word is a Messiah who takes the form of a servant, and a church that eventually had to admit the Atlantic trade could not survive the gospel it claimed to hold.