Goliath
Goliath is described in the biblical Book of Samuel as a Philistine giant defeated by the young David in single combat. The story signified Saul's unfitness to rule, as Saul himself should have fought for the Kingdom of Israel.
Goliath
The underlying purpose of the story of Goliath is to show that Saul is not fit to be king (and that David is). Saul was chosen to lead the Israelites against their enemies, but when faced with Goliath he refuses to do so; Goliath is a giant, and Saul is a very tall man. Saul's exact height is not given, but he was a head taller than anyone else in all Israel (1 Samuel 9:2), which implies he was over tall and supposed to be the obvious challenger for Goliath, yet, David is the one who eventually defeated him. Also, Saul's armour and weaponry are apparently no worse than Goliath's (and David, of course, refuses Saul's armour in any case). "David declares that when a lion or bear came and attacked his father's sheep, he battled against it and killed it, [but Saul] has been cowering in fear instead of rising up and attacking the threat to his sheep (i.e. Israel)."