2 Samuel 16:21-17:4

ASV(i) 21 And Ahithophel said unto Absalom, Go in unto thy father's concubines, that he hath left to keep the house; and all Israel will hear that thou art abhorred of thy father: then will the hands of all that are with thee be strong. 22 So they spread Absalom a tent upon the top of the house; and Absalom went in unto his father's concubines in the sight of all Israel. 23 And the counsel of Ahithophel, which he gave in those days, was as if a man inquired at the oracle of God: so was all the counsel of Ahithophel both with David and with Absalom.
17 1 Moreover Ahithophel said unto Absalom, Let me now choose out twelve thousand men, and I will arise and pursue after David this night: 2 and I will come upon him while he is weary and weak-handed, and will make him afraid; and all the people that are with him shall flee; and I will smite the king only; 3 and I will bring back all the people unto thee: the man whom thou seekest is as if all returned: [so] all the people shall be in peace. 4 And the saying pleased Absalom well, and all the elders of Israel.