Concept:God revealed to Joshua that Israel's defeat at Ai was caused by hidden sin in the camp, so Joshua was to rise and prepare the people for God's correction.
Explanation:Israel lost the battle at Ai because Achan had secretly taken some of the devoted things that God commanded to be destroyed (Joshua 7:1).
Joshua was deeply distressed and fell on his face before the Lord.
God asked him, "Arise, why have you thus fallen upon your face?" (Joshua 7:10).
The defeat was not due to a weak army or poor military strategy, but due to sin among the people.
God instructed Joshua, "Up, sanctify the people, and say, 'Sanctify yourselves for tomorrow'" (Joshua 7:13).
Sanctification was needed before God would again fight for Israel.
Joshua was not told to send more soldiers, encourage the people, or merely pray at that moment.
His first duty was to sanctify the people so the devoted things could be removed from the camp.
Answer:D. sanctify the people