Joshua 6:17-19

And the city and all that is within it shall be devoted to the LORD for destruction. Only Rahab the prostitute and all who are with her in her house shall live, because she hid the messengers whom we sent. But you, keep yourselves from the things devoted to destruction, lest when you have devoted them you take any of the devoted things and make the camp of Israel a thing for destruction and bring trouble upon it. But all silver and gold, and every vessel of bronze and iron, are holy to the LORD; they shall go into the treasury of the LORD.”