Judges 7:5-6

So he brought the troops down to the water, and ADONAI said to Gideon, “You are to set apart everyone who laps the water with his tongue, as a dog laps, and everyone who bows down on his knees to drink.” Now the number of those who lapped, putting their hand to their mouth, was 300 men, but all the rest of the people bowed down on their knees to drink water.