2 Samuel 17:14, 23

And Absalom and all the men of Israel said, The counsel of Hushai the Archite is better than the counsel of Ahithophel. For Jehovah had ordained to defeat the good counsel of Ahithophel, to the intent that Jehovah might bring evil upon Absalom.

And when Ahithophel saw that his counsel was not followed, he saddled his ass, and arose, and gat him home, unto his city, and set his house in order, and hanged himself; and he died, and was buried in the sepulchre of his father.