"In addition to being the middle chapter of 1 Samuel, chapter 16 is pivotal in another way as well: Its first half (vv. 1-13), ending with a statement concerning David's reception of the Spirit of God, describes David's anointing as ruler of Israel to replace Saul; its second half (vv. 14-23), beginning with a statement concerning Saul's loss of the Spirit and its replacement with an evil spirit' sent by God, describes David's arrival in the court of Saul. Thus the juxtaposition of vv. 13 and 14 delineates not only the transfer of the divine blessing and empowerment from Saul to David but also the beginning of the effective displacement of Saul by David as king of Israel. The transition at vv. 13-14 can thus be arguably defined as the literary, historical, and theological crux of 1 Samuel as a whole."178
Verse 14 describes God's relationship to Saul following the Lord's rejection of him. Yahweh had less and less contact with His faithless representative. His empowering Spirit left him without the divine enablement that he had once enjoyed (cf. Judg. 9:23; 16:20; 1 Kings 22:21-23; Ps. 51:11).
"When YHWH's Spirit came upon David his anointer [Samuel] left, leaving him in good hands. When YHWH's Spirit left Saul an evil spirit came upon him, leaving him in dire straits."179
The evil spirit that Yahweh permitted to trouble Saul has been the subject of considerable interest among Bible students. It may have been a spirit of discontent (cf. Judg. 9:23), a demon who afflicted him periodically (cf. 1 Kings 22:20-23), or a demon who indwelt him from then on.180In any case it was a discipline for departing from God. When people depart from God, their troubles really begin.
"Saul's evil bent was by the permission and plan of God. We must realize that in the last analysis all penal consequences come from God, as the Author of the moral law and the one who always does what is right."181
The writer mentioned Saul's fits of terror to explain, in addition to his deteriorating mental state, why Saul called for a musician and how David gained access to the royal court. It is tempting to suggest that Saul's mental problems may have resulted from his spiritual rebellion, which is common, but the text does not state that connection outright. Apparently some people already regarded David as a mighty man of valor and a warrior (v. 18) because he had single-handedly defeated lions and bears (17:34-35). Most important, the Lord was with David.182The fact that Jesse could provide a donkey suggests that he was fairly prosperous since this is how the more wealthy classes travelled in Israel (v. 20). Yet David's family was not outstanding in Israel (cf. 18:18).
Initially Saul loved David greatly, as Jonathan did (cf. 18:1, 3; 20:17). However, Saul's attitude would change. The king appointed an armorbearer to that position because of his courage, his ability to handle weapons, and his ability to get along with the king. David was probably a teenager at this time since he was 30 when he began to reign (2 Sam. 5:4). He was not Saul's bodyguard. He just helped the king handle his armor. Whatever kind of spirit afflicted Saul, David's sweet music reduced its ill effects. Saul was becoming dependent on the one who would replace him.
God was elevating David from the ranks of a shepherd of sheep (v. 11) to become the shepherd of His people, and David's musical ability (v. 18) enabled him to lead the Israelites in the worship of Yahweh later.
"This story of how David first met Saul and how he came to the royal court makes two points. The first is that David did not engineer it. David was no ruthlessly ambitions man, determined to rise up the social ladder--any more than Saul himself had been (cp. chapter 9). David's hands were clean. The second point is that God overruled to bring David to court, through the sheer chance (as it seemed) that one of Saul's courtiers knew something about him and brought him to Saul's attention [cf. Joseph]. So it was God, not David, who was responsible for the young man's first steps towards the throne."183
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