1 Samuel 17:16

And the Philistine drew near morning and evening, and presented himself forty days.

The Philistine of the verse is Goliath, who came forward and presented himself to defy and challenge Israel morning and evening for forty days. His prolonged boasting filled Israel with terror and made Saul greatly afraid, so that no Israelite dared or was willing to answer his challenge. The daily challenge stirred David to zeal for God's honor and for his people.

David's courage in facing the champion came from faith in God. He killed the Philistine champion and later relied on the memory of that victory when he took Goliath's sword, though his trust faltered during later danger.

Goliath exemplifies defiant, boastful opposition. His repeated self-presentation should not be imitated by provoking religious discussion and then trusting in personal arguments. David's example teaches that God's cause should be defended with humility and reliance on God rather than self-confidence.