"and you shall hang him": "him," without his garments (i.e., naked). "him," and not scheming witnesses against him (viz. Devarim 19:19). "him": We are hereby taught that two are not judged (for such an offense) on one day.
"and you shall hang him on eitz" [("eitz" can mean either wood or tree)]: "eitz" that is not rooted (i.e., wood), and not "eitz" that is rooted (i.e., a tree). — But perhaps it means "eitz" that is rooted! — It is, therefore, (to negate this) written (Ibid. 23) "but you shall bury it" — what lacks only burial, to exclude that (a rooted eitz), which lacks cutting and burial.