This is the central unit of chapters 5-20, and its central focus is the judgment that Hushai's advice was better than Ahithophel's (17:14). This advice is the pivot on which the fortunes of David swung in his dealings with Absalom.
Hushai was loyal to David primarily because David was the Lord's anointed (v. 18). His words to Absalom implied that he was supporting the revolution, but everything that Hushai said could have been taken as supporting David, which he did. They are masterful double entendre. He was really serving David in the presence of his son Absalom (v. 19).
"Hushai has kept his integrity, Absalom has been blinded by his own egoism, and the reader is permitted to see one example of the outworking of God's providence."248
In the ancient East people regarded the public appropriation of a king's concubines as an act that signaled the transfer of power to his successor.249Here Absalom broke the Mosaic Law (Lev. 18:7-8) to gain power. By following Ahithophel's advice Absalom brought about one of the judgments God had predicted would come on David for his sin (12:11-12). This act was also a great insult to David, and it jeopardized Absalom's inheritance rights (cf. Reuben's similar sin, Gen. 35:22; 49:3-4). The king was reaping what he had sown (Gal. 6:7). Absalom's immorality may have taken place on the very roof where David had committed adultery (cf. 11:2).
"David had illicitly slept with a woman who was not his wife (cf. 11:4), and now his son is counseled to follow in his father's footsteps."250
In 17:9 Hushai warned that if only a small group of Absalom's men pursued David and David defeated them, the news would spread that Absalom had lost the battle. The people would then side with David. He proposed the ultimate flattery, namely, that Absalom himself should lead his troops into battle (v. 11). Yahweh sought to bring calamity on Absalom (v. 14) because Absalom sought to overthrow the Lord's anointed.
Enrogel (v. 17) was just south of Zion near where the Hinnom and Kidron Valleys join.251Ahithophel may have believed that Hushai's advice would result in Absalom's defeat and David's ultimate return to Jerusalem,252or he may have committed suicide out of humiliation (v. 23).
"All the utterly real issues between people and people and between God and people that swirl throughout II Samuel 9-20, I Kings 1-2 also swirl about Jesus as he moves toward the cross. One must think that the Gospel writers were acutely aware of this when they depicted Jesus' Maundy Thursday walk to the Mount of Olives in ways so graphically reminiscent of the passion' of the first Meshiachin II Samuel 15:13-37. Even the detail of Judas' betrayal of Jesus, and his subsequent suicide, have no remote parallel anywhere in Scripture, with the remarkable exception of Ahithophel, who betrayed the Lord's anointed and thus opened the door to suicidal despair (II Samuel 17:23)."253
Mahanaim on the Jabbok in Transjordan had been Ish-bosheth's capital (2:8). Probably David went there because the inhabitants favored him for his goodness to Mephibosheth, Saul's grandson. Amasa was the son of Jithra (or Jether) an Ishmaelite (not Israelite; cf. 1 Chron. 2:17) and the son of Joab's cousin Abigail. Absalom's army also camped in Transjordan in the Gilead hills probably south of Mahanaim.
Those who helped David included Shobi (v. 27), the son of Nahash, who had been king of Ammon, and who was probably the brother of Hanun, the present Ammonite king who had humiliated David's well-wishers (ch. 10). Ammon was presently subservient to Israel. David and Joab had subdued Ammon about 14 years earlier (12:26-31). Machir had been the host of Mephibosheth before David assumed his support and moved him to Jerusalem from Lo-debar (9:1-5). Barzillai was a wealthy supporter of David from Rogelim, a town farther to the north in Gilead. Shobi, Machir, and Barzillai demonstrate other characteristics of true friends: they initiated help for David and supplied him abundantly with his needs and wants.
If all Christians are God's anointed (and we are, 1 John 2:27), even though former friends disappoint, forsake, and betray us, the Lord will preserve and protect us (cf. Heb. 13:5-6). He will even raise us from the dead to keep His promises to us (cf. Heb. 11:19). Our responsibility is simply to follow the Lord faithfully in spite of opposition, as we see David doing in this story.