2 Samuel 16:18-22

So Hushai said to Absalom, “No! For whomever the Lord, this people, and all the men of Israel have chosen, his I shall be, and with him I shall remain.

Besides, whom should I serve? Should I not serve in the presence of his son? Just as I have served in your father’s presence, so I shall be in your presence.”

Then Absalom said to Ahithophel, “Give your advice. What should we do?”

Ahithophel said to Absalom, “Have relations with your father’s concubines, whom he has left behind to take care of the house; then all Israel will hear that you have made yourself repulsive to your father. The hands of all who are with you will also be strengthened.”

So they pitched a tent for Absalom on the roof, and Absalom had relations with his father’s concubines in the sight of all Israel.