Judges 7:4-8

But the LORD said to Gideon, “There are still too many men. Take them down to the water, and I will thin them out for you there. If I say, ‘This one shall go with you,’ he shall go; but if I say, ‘This one shall not go with you,’ he shall not go.” So Gideon took the men down to the water. There the LORD told him, “Separate those who lap the water with their tongues as a dog laps from those who kneel down to drink.” Three hundred of them drank from cupped hands, lapping like dogs. All the rest got down on their knees to drink. The LORD said to Gideon, “With the three hundred men that lapped I will save you and give the Midianites into your hands. Let all the others go home.” So Gideon sent the rest of the Israelites home but kept the three hundred, who took over the provisions and trumpets of the others. Now the camp of Midian lay below him in the valley.