Joshua 7:9

5 And the men of Ai struck down about thirty-six of them, chasing them from the gate as far as the quarries and striking them down on the slopes. So the hearts of the people melted and became like water.

6 Then Joshua tore his clothes and fell facedown before the ark of the LORD until evening, as did the elders of Israel; and they all sprinkled dust on their heads.

7 “O, Lord GOD,” Joshua said, “why did You ever bring this people across the Jordan to deliver us into the hand of the Amorites to be destroyed? If only we had been content to stay on the other side of the Jordan!

8 O Lord, what can I say, now that Israel has turned its back and run from its enemies?

9 When the Canaanites and all who live in the land hear about this, they will surround us and wipe out our name from the earth. Then what will You do for Your great name?”

10 But the LORD said to Joshua, “Stand up! Why have you fallen on your face?

11 Israel has sinned; they have transgressed My covenant that I commanded them, and they have taken some of what was devoted to destruction. Indeed, they have stolen and lied, and they have put these things with their own possessions.

12 This is why the Israelites cannot stand against their enemies. They will turn their backs and run from their enemies, because they themselves have been set apart for destruction. I will no longer be with you unless you remove from among you whatever is devoted to destruction.

13 Get up and consecrate the people, saying, ‘Consecrate yourselves for tomorrow, for this is what the LORD, the God of Israel, says: Among you, O Israel, there are things devoted to destruction. You cannot stand against your enemies until you remove them.

Read all of Joshua 7