His body shall not remain all night upon the tree, but thou shalt in any wise bury him that day; (for he that is hanged is accursed of God;) that thy land be not defiled, which the LORD thy God giveth thee for an inheritance.

you must not leave the body on the tree overnight, but you must be sure to bury him that day, because anyone who is hung on a tree is under God’s curse. You must not defile the land that the LORD your God is giving you as an inheritance.