Six cubits — At least, nine feet, nine inches high. And this is not strange; for besides the giants mentioned in Scripture, Herodotus, Diodorus Siculus, and Pliny, make mention of persons seven cubits high.
Related Commentaries of 1 Samuel 17:4
1 Samuel 17:4
4 And there went out a champion out of the camp of the Philistines, named Goliath, of Gath, whose height was six cubits and a span.