2 Samuel 16:15-23 NIV
Meanwhile, Absalom and all the men of Israel came to Jerusalem, and Ahithophel was with him. Then Hushai the Arkite, David’s confidant, went to Absalom and said to him, “Long live the king! Long live the king!”
Absalom said to Hushai, “So this is the love you show your friend? If he’s your friend, why didn’t you go with him?”
Hushai said to Absalom, “No, the one chosen by the LORD, by these people, and by all the men of Israel—his I will be, and I will remain with him. Furthermore, whom should I serve? Should I not serve the son? Just as I served your father, so I will serve you.”
Absalom said to Ahithophel, “Give us your advice. What should we do?”
Ahithophel answered, “Sleep with your father’s concubines whom he left to take care of the palace. Then all Israel will hear that you have made yourself obnoxious to your father, and the hands of everyone with you will be more resolute.” So they pitched a tent for Absalom on the roof, and he slept with his father’s concubines in the sight of all Israel.
Now in those days the advice Ahithophel gave was like that of one who inquires of God. That was how both David and Absalom regarded all of Ahithophel’s advice.
NIV: New International Version