Though Saul had given David permission to accept Goliath's challenge, the king had small hope that David would be successful 647 in his courageous undertaking. Command was given to clothe the youth in the king's own armor. The heavy helmet of brass was put upon his head, and the coat of mail was placed upon his body; the monarch's sword was at his side. Thus equipped, he started upon his errand, but erelong began to retrace his steps. The first thought in the minds of the anxious spectators was that David had decided not to risk his life in meeting an antagonist in so unequal an encounter. But this was far from the thought of the brave young man. When he returned to Saul he begged permission to lay aside the heavy armor, saying, "I cannot go with these; for I have not proved them." He laid off the king's armor, and in its stead took only his staff in his hand, with his shepherd's scrip and a simple sling. Choosing five smooth stones out of the brook, he put them in his bag, and, with his sling in his hand, drew near to the Philistine. The giant strode boldly forward, expecting to meet the mightiest of the warriors of Israel. His armor-bearer walked before him, and he looked as if nothing could withstand him. As he came nearer to David he saw but a stripling, called a boy because of his youth. David's countenance was ruddy with health, and his well-knit form, unprotected by armor, was displayed to advantage; yet between its youthful outline and the massive proportions of the Philistine, there was a marked contrast.

Skønt kong Saul havde givet David tilladelse til at tage imod Goliats udfordring, nærede han ikke store forhåbninger til, at Davids dristige forehavende ville lykkes. Der blev givet befaling til, at David skulle iføres kongens egen rustning. Man satte den tunge kobberhjelm på hans hoved, iførte ham brynjen og spændte kongens sværd ved hans side. I denne udrustning gik han ud for at møde fjenden, men et øjeblik efter kom han tilbage igen. De ængstelige tilskuere troede først, at David havde ombestemt sig og ikke ville vove livet i en så ulige kamp; men denne tanke var overhovedet ikke faldet den tapre, unge mand ind. Da han kom hen til Saul, bad han om at måtte tage den tunge rustning af. Han sagde: "Jeg kan ikke gå dermed, thi jeg har aldrig prøvet det før!" Han afførte sig kongens rustning og tog kun sin stav, sin hyrdetaske og en primitiv slynge med sig. Så udsøgte han sig fem glatte sten i flodlejet, lagde dem i sin taske og gik filisteren i møde med sin slynge i hånden. Kæmpen satte sig i bevægelse i den tro, at han skulle kæmpe med israelitternes vældigste kriger. Hans skjolddrager gik foran ham, og han så ud, som om intet kunne modstå ham. Da han kom i nærheden af David, så han blot en ganske ung mand; man kaldte ham en dreng, fordi han var så ung. David havde en sund kulør, og han havde heller ingen grund til at skamme sig over sit velskabte legeme, som var fuldstændig ubeskyttet. Men der var alligevel en iøjnefaldende modsætning imellem den unge mand og den kolossale filister.