The practice of exposure by hanging on a tree was a wartime practice well known in Assyria and Egypt. It was a characteristic treatment of enemy leaders, especially those whom the victor wanted to use as an example.1 In the Bible, it is also found in relation to criminal penalties (Deuteronomy 21:22). The biblical symbolism of hanging someone on a tree was to show that the person ought to be considered as cursed by God. Thus, the king of Ai and all people of Canaan stand under the Lord’s curse and judgment.2
29 And he hanged the king of Ai on a tree until evening. And at sunset Joshua commanded, and they took his body down from the tree and threw it at the entrance of the gate of the city and raised over it a great heap of stones, which stands there to this day.