Judges 7:5

So he brought down the people unto the water; and the Lord said unto Gideon, Every one that lappeth of the water with his tongue, not taking the time to kneel down, but quickly scooping up some water with the hollow hand and drinking from its cuplike curve, as a dog lappeth, him shalt thou set by himself, in one division; likewise every one that boweth down upon his knees to drink. They were here under no constraint of any kind, and would show their natural characteristics very plainly.