2 Samuel 17:21-25

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.”

Then David and all the people who were with him set out and crossed the Jordan; by dawn not even one remained who had not crossed the Jordan.

Now when Ahithophel saw that his advice had not been followed, he saddled his donkey and set out and went to his home, to his city, and set his house in order, and hanged himself; so he died and was buried in his father’s grave.

Then David came to Mahanaim. And Absalom crossed the Jordan, he and all the men of Israel with him.

Absalom put Amasa in command of the army in place of Joab. Now Amasa was the son of a man whose name was Ithra the Israelite, who had relations with Abigail the daughter of Nahash, sister of Zeruiah, Joab’s mother.