Complete Commentary on the Whole Bible, by Matthew Henry, at sacred-texts.com
2 Kings (2 Samuel)
(v. 1-21) Ahithophel's counsel overthrown.
(Sa2 17:22-29) He hangs himself, Absalom pursues David.
2 Kings (2 Samuel) 17:1
Here was a wonderful effect of Divine Providence blinding Absalom's mind and influencing his heart, that he could not rest in Ahithophel's counsel, and that he should desire Hushai's advice. But there is no contending with that God who can arm a man against himself, and destroy him by his own mistakes and passions. Ahithophel's former counsel was followed, for God intended to correct David; but his latter counsel was not followed, for God meant not to destroy him. He can overrule all counsels. Whatever wisdom or help any man employs or affords, the success is from God alone, who will not let his people perish.
2 Kings (2 Samuel) 17:22
Ahithophel hanged himself for vexation that his counsel was not followed. That will break a proud man's heart which will not break a humble man's sleep. He thought himself in danger, concluding, that, because his counsel was not followed, Absalom's cause would fail; and to prevent a possible public execution, he does justice upon himself. Thus the breath is stopped, and the head laid low, from which nothing could be expected but mischief. Absalom chased his father. But observe how God sometimes makes up to his people that comfort from strangers, which they are disappointed of in their own families. Our King needs not our help; but he assures us, that what we do for the least of his brethren, who are sick, poor, and destitute, shall be accepted and recompensed as if done to himself.