David's Victory Over Goliath

First, in vv 31-33 - Saul told David that he was unable to defeat the giant, Goliath.

Second, in vv 34-37 - David was confident of the Lord's ability to deliver him from Goliath.

Third, in vv 38-39 - David rejected Saul's advice to fight the giant in the strength of his own flesh.

Fourth, in vv 40-44 - Goliath tried to intimidate David with his seemingly superior strength.

Fifth, in vv 45-47 - David's victory over Goliath demonstrated that the Lord Himself delivers His people from gigantic, formidable enemies.

Sixth, in vv 48-51 - David defeated Goliath by mounting an attack and going on the offensive against him.