What does Judges 7:6 mean?

Now therefore proclaim in the ears of the people, saying, ‘Whoever is fearful and trembling, let him return and depart from Mount Gilead.’” So twenty-two thousand of the people returned, and ten thousand remained.

Yahweh said to Gideon, “There are still too many people. Bring them down to the water, and I will test them for you there. It shall be, that those whom I tell you, ‘This shall go with you,’ the same shall go with you; and whoever I tell you, ‘This shall not go with you,’ the same shall not go.”

So he brought down the people to the water; and Yahweh said to Gideon, “Everyone who laps of the water with his tongue, like a dog laps, you shall set him by himself; likewise everyone who bows down on his knees to drink.”

Yahweh said to Gideon, “By the three hundred men who lapped will I save you, and deliver the Midianites into your hand. Let all the other people go, each to his own place.”

So the people took food in their hand, and their trumpets; and he sent all the men of Israel every man to his tent, but retained the three hundred men; and the camp of Midian was beneath him in the valley.

That same night, Yahweh said to him, “Arise, go down into the camp; for I have delivered it into your hand.