In Judges 7, God is reducing the number of men Gideon will use to fight the Midianites. God does this twice in this chapter. First, in v3 God tells Gideon to whosoever is fearful and afraid should return. This brought the number down to 10,000. Second, God had the men drink water. Gideon was to select 300 men that lapped to go into battle and those who bowed down upon their knees were sent back to the tents.
Researchers from Virginia Tech in 2015 (Findings published in Proceedings of the National Academy of Sciences) studied the mechanism which dogs drink and why the "lapping of the tongue" is necessary. "Dogs and cats are biting animals and neither have full cheeks. But without cheeks, they can’t create suction to drink — as people, horses, and elephants do. Instead, they use their tongues to quickly raise water upward through a process involving inertia."
Those who bowed down upon their knees did NOT use their hands to drink water, but put their faces to the water to create suction and did not able to pay attention to their surroundings.
The 300 men that were chosen by God lapped with their tongue like a dog (v5) and lapped putting their hands to their mouth (v6) which was not creating suction to drink water.
Did this style of drinking allow the men to keep a watchful eye as they brought the water in cupped hands to their mouth?
Did God choose this group because they were vigilant which is a favorable trait?
If God choose this group because they were weak, is this consistent with v3 where God choose the fearless, courageous and brave (antonyms for fearful and afraid)?
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, as a dog lappeth, him shalt thou set by himself; likewise every one that boweth down upon his knees to drink.
6 And the number of them that lapped, putting their hand to their mouth, were three hundred men: but all the rest of the people bowed down upon their knees to drink water.
7 And the Lord said unto Gideon, By the three hundred men that lapped will I save you, and deliver the Midianites into thine hand: and let all the other people go every man unto his place.