2 Samuel 17:21
ESV
After they had gone, the men came up out of the well, and went and told King David. They said to David, "Arise, and go quickly over the water, for thus and so has Ahithophel counseled against you."
NIV
After they had gone, the two climbed out of the well and went to inform King David. They said to him, "Set out and cross the river at once; Ahithophel has advised such and such against you."
NASB
It came about after they had departed, that they came up out of the well and went and reported to King David; and they said to David, 'Set out and cross over the water quickly, because this is what Ahithophel has advised against you.'
CSB
After they had gone, Ahimaaz and Jonathan climbed out of the well and went and informed King David. They told him, "Get up and immediately ford the river, for Ahithophel has given this advice against you."
NLT
Then the two men crawled out of the well and hurried on to King David. 'Quick!' they told him, 'cross the Jordan tonight!' And they told him how Ahithophel had advised that he be captured and killed.
KJV
And it came to pass, after they were departed, that they came up out of the well, and went and told king David, and said unto David, Arise, and pass quickly over the water: for thus hath Ahithophel counselled against you.
NKJV
Now it came to pass, after they had departed, that they came up out of the well and went and told King David, and said to David, “Arise and cross over the water quickly. For thus has Ahithophel advised against you.”
What does 2 Samuel 17:21 mean?
Absalom is strategic, patient, and careful. He waited two years to murder his brother (2 Samuel 13:23–29). He worked for four years to win the people's hearts before he declared himself king and forced David into exile (2 Samuel 15:1–11). He recruited David's trusted advisor Ahithophel to help him keep the kingdom he's trying to usurp (2 Samuel 15:12; 16:20–23).David is strategic, as well. In just one day, he has created a network of spies and informants, including two priests, their sons, and an old friend (2 Samuel 15:24–29, 32–37).
David's friend Hushai was there when Absalom's Ahithophel suggested immediately chasing down David and his people (2 Samuel 17:1–4). Hushai convinced Absalom to wait—taking advantage of his preference for slow, thoughtful action—so David had more time to regroup. The priests sent a servant woman to tell their sons Jonathan and Ahimaaz. A young man saw them, and Absalom sent guards to track the men down. Thanks to another woman, they escaped by hiding in a well (2 Samuel 17:5–13, 15–20).
The woman has misled the guards, and Jonathan and Ahimaaz crawl out of the well. They resume their trek to David, waiting on the near side of the Jordan River with his servants, and tell him Hushai's message that Absalom is preparing an army; they need to get cross the river and get to safety. By the next morning, David's people are safe (2 Samuel 17:22).
David and his people aren't safe because Hushai is a better advisor than Ahithophel. Nor is it because the priests and their sons are particularly loyal and clever. They're safe because God is for David and against Absalom (2 Samuel 17:14). When Ahithophel learns that Absalom took Hushai's advice and not his, he seems to understand this. He goes home, puts his house in order, and hangs himself (2 Samuel 17:23).