Defeating Our Own Worst Enemy

Bottom line: We overcome our own worst enemy (self) when we release our perceived enemy instead of taking revenge.

David's greatest victory wasn't won on a battlefield. David's greatest victory wasn't defeating Goliath, or, for that matter, any victory David ever won over someone else. His greatest victory was won over himself not on a battlefield but in a cave. David overcame his flesh nature's desire for revenge and instead released Saul and trusted God to avenge him.