Reference

Judges 20:12-28
When God Says "GO!"

And the tribes of Israel sent men through all the tribe of Benjamin, saying, What wickedness is this that is done among you? Now therefore deliver us the men, the children of Belial, which are in Gibeah, that we may put them to death, and put away evil from Israel. But the children of Benjamin would not hearken to the voice of their brethren the children of Israel: But the children of Benjamin gathered themselves together out of the cities unto Gibeah, to go out to battle against the children of Israel. And the children of Benjamin were numbered at that time out of the cities twenty and six thousand men that drew sword, beside the inhabitants of Gibeah, which were numbered seven hundred chosen men. Among all this people there were seven hundred chosen men lefthanded; every one could sling stones at an hair breadth, and not miss. And the men of Israel, beside Benjamin, were numbered four hundred thousand men that drew sword: all these were men of war. And the children of Israel arose, and went up to the house of God, and asked counsel of God, and said, Which of us shall go up first to the battle against the children of Benjamin? And the LORD said, Judah shall go up first. And the children of Israel rose up in the morning, and encamped against Gibeah. And the men of Israel went out to battle against Benjamin; and the men of Israel put themselves in array to fight against them at Gibeah. And the children of Benjamin came forth out of Gibeah, and destroyed down to the ground of the Israelites that day twenty and two thousand men. And the people the men of Israel encouraged themselves, and set their battle again in array in the place where they put themselves in array the first day. (And the children of Israel went up and wept before the LORD until even, and asked counsel of the LORD, saying, Shall I go up again to battle against the children of Benjamin my brother? And the LORD said, Go up against him.) And the children of Israel came near against the children of Benjamin the second day. And Benjamin went forth against them out of Gibeah the second day, and destroyed down to the ground of the children of Israel again eighteen thousand men; all these drew the sword. Then all the children of Israel, and all the people, went up, and came unto the house of God, and wept, and sat there before the LORD, and fasted that day until even, and offered burnt offerings and peace offerings before the LORD. And the children of Israel enquired of the LORD, (for the ark of the covenant of God was there in those days, And Phinehas, the son of Eleazar, the son of Aaron, stood before it in those days,) saying, Shall I yet again go out to battle against the children of Benjamin my brother, or shall I cease? And the LORD said, Go up; for to morrow I will deliver them into thine hand. - Judges 20:12-28