David vs Goliath

[1 Sam. !6:40] And he took his staff in his hand, and chose him five smooth stones out of the brook, and put them in a shepherd's bag which he had, even in a scrip; and his sling was in his hand: and he drew near to the Philistine.
Saul, because he was Israel’s first king had to face many odds – a disorganized people divided into several tribal groups. These had first to be united. They were a people with no military training and with no up-to-date weapons, with powerful enemies round, about, and experiencing conflict with the old power structure of the judges.
David had the advantage also of being trained in Saul’s royal circle as an armourbearer and a commander over the men of war, as well as being the king’s son-in-law. Consequently, from an organizational standpoint David did not have to start from scratch; much of what Saul had built up was now available for David’s use.
David was primarily recruited into Saul’s military service, true to what was said about Saul in 14:52. That Saul later set him over the men of war (18:5) to become a commander of a thousand (18: 13) speaks in support of this tradition. According to the other tradition, the musician-cum-shepherd David was brought to Saul’s court mainly to play music whenever the evil spirit tormented Saul verse 23. Only in 17:32-54 is David described as a boy.
David’s experiences of valor hitherto have been with lions and bears. There were two different reencounters, for those animals prowl alone. The bear must have been a Syrian bear, which is believed to be a distinct species, or perhaps a variety, of the brown bear. The beard applies to the lion alone. Those feats seem to have been performed with no weapons more effective than the rude staves and stones of the field, or his shepherd's crook.
David choose to stand up for G-d’s honor though a youth, he was the only one to show faith and courage. David went in the name of the L-rd of host.
The shepherd’s scrip is a bag made of skin, carried over the shepherd’s shoulder by means of a heavy cord, in which he carries his supply of bread, olives, cheese, dried figs and parched grain. Sometimes these bags are crudely made of raw skins, but quite often they are made of well-tanned and attractively dyed leather with exquisitely embroidered designs. Merchants carry their money and other valuables in scrip’s. Shepherds use it not only to carry supplies for their own needs but also emergency items for the care of injured or sick sheep, since they must be both physician and surgeon to their flocks. The emphasis here is that it is not so much David who is going to fight, but the L-rd.
Brook - wady.
Bag or scrip for containing his daily food.
The sling consisted of a double rope with a thong, probably of leather, to receive the stone. The slinger held a second stone in his left hand. David chose five stones, as a reserve, in case Goliath four brothers came at him. Shepherds in the East carry a sling and stones still, for the purpose of driving away, or killing, the enemies that prowl about the flock.
When the two champions met, they generally made each of them a speech, and sometimes recited some verses, filled with allusions and epithets of the most opprobrious kind, hurling contempt and defiance at one another. This kind of abusive dialogue is common among the Arab combatants still. David's speech, however, presents a striking contrast to the usual strain of these invectives. It was full of pious trust, and to G-d he ascribed all the glory of the triumph he anticipated.
Sounds kind of like politicians today, don’t it.
David cuts off Goliath’s head with the enemy’s own sword. That all this assembly may know that the L-rd saves not with sword and spear; for the battle is the L-rd’s!
Do you have a Goliath in your life? Turn it over to G-d and let Him fight it for you!
The story of David and Goliath stands for all times as a paradigm for the encounter between the power of the Spirit, which is the power of G-d, and the power of the flesh, which is the power of the world. It is the encounter between righteousness and unrighteousness, liberation and oppression. The power of the Spirit will ultimately triumph in human history. That is the vital message of this paradigm.