Joshua 7:13

Up, sanctify the people, and say, Sanctify yourselves against to morrow: for thus saith the LORD God of Israel, There is an accursed thing in the midst of thee, O Israel: thou canst not stand before thine enemies, until ye take away the accursed thing from among you.

Sanctify yourselves — Purify yourselves from that defilement which you have all in some sort contracted by this accursed fact, and prepare yourselves to appear before the Lord, expecting the sentence of God for the discovery and punishment of the sin, and that the guilty person might hereby be awakened, and brought to a free confession of his fault. And it is a marvellous thing that Achan did not on this occasion acknowledge his crime; but this is to be imputed to the heart-hardening power of sin, which makes men, grow worse and worse; to his pride, being loath to take to himself the shame of such a mischievous and infamous action; and to his vain conceit, whereby he might think others were guilty as well as he, and some of them might be taken, and he escape.