Judges 7:4-7

Then the LORD said to Gideon, “There are still too many people; bring them down to the water and I will test them for you there. Therefore it shall be that he of whom I say to you, ‘This one shall go with you,’ he shall go with you; but everyone of whom I say to you, ‘This one shall not go with you,’ he shall not go.” So he brought the people down to the water, and the LORD said to Gideon, “You shall separate everyone who laps the water with his tongue as a dog laps, as well as everyone who kneels down to drink.” Now the number of those who lapped [the water], putting their hand to their mouth, was three hundred men, but all the rest of the people kneeled down to drink water. And the LORD told Gideon, “With the three hundred men who lapped I will rescue you, and will hand over the Midianites to you. Let all the other people go, each man to his home.”