2 Samuel 18:5-10
English Standard Version
6So the army went out into the field against Israel, and the battle was fought in the forest of Ephraim.
7And the men of Israel were defeated there by the servants of David, and the loss there was great on that day, twenty thousand men.
8The battle spread over the face of all the country, and the forest devoured more people that day than the sword.
9And Absalom happened to meet the servants of David. Absalom was riding on his mule, and the mule went under the thick branches of a great oak, and his head caught fast in the oak, and he was suspended between heaven and earth, while the mule that was under him went on.
10And a certain man saw it and told Joab, "Behold, I saw Absalom hanging in an oak."
