Shofetim 7:5-6

So he brought down haAm unto the mayim; and HASHEM said unto Gid'on, Every one that laps the mayim with his leshon, as a kelev laps, him shalt thou separate by himself; likewise every one that kneels down upon his knees to drink. And the number of the ones lapping, putting their yad to their mouth, were three hundred ish; but all the rest of haAm kneeled down upon their knees to drink mayim.