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.
Biblical and Quranic narratives
The story appears in 1 Samuel 8–12 and 17:1–58. The Prophet Samuel is petitioned by the Israelites for a king. God sends Samuel to appoint Saul as king, although with the warning that kings only take from their people. At least a few people are not happy with Samuel's choice, but Saul then prophecises and wins some victories, so the people embrace him. Later Saul falls out of God's favor and God promises to appoint someone else as king. The Philistines attack and are bolstered by the fear engendered by their champion Goliath, a giant. God sends Samuel to recruit David, who kills Goliath. David eventually goes on to become Israel's new king.