Deut 13:16-17

16 All of its spoil you shall gather into its public square; then burn the town and all its spoil with fire, as a whole burnt offering to the Lord your God. It shall remain a perpetual ruin, never to be rebuilt. 17 Do not let anything devoted to destruction stick to your hand, so that the Lord may turn from his fierce anger and show you compassion, and in his compassion multiply you, as he swore to your ancestors,