Joshua 6:17-18

17The city and everything that is in it shall be under the ban [that is, designated to be destroyed as a form of tribute] to the Lord; only Rahab the prostitute and all [the people] who are with her in her house shall [be allowed to] live, because she hid and protected the messengers (scouts) whom we sent.

18But as for you, keep yourselves [away] from the things under the ban [which are to be destroyed], so that you do not covet them and take some of the things under the ban [for personal gain], and put the camp of Israel under the ban (doomed to destruction), and bring disaster upon it.