Deutéronome 21:23

his dead body shall not remain upon the beam, but he shall be certainly buried on the same day; for it is execrable before God to hang a man, but that his guilt gave occasion for it; and because he was made in the image of God, you shall bury him at the going down of the sun, lest wild beasts abuse him, and lest you overspread your land, which the Lord your God giveth you to possess, with the dead bodies of criminals.

a hanged man is a curse of God since he blasphemed against God . But the simple explanation is that God is the source of the curse, which will descend everywhere close to the hanged man. There is a mysterious aspect to this curse which attaches itself to human life. Accordingly, Scripture says you shall not defile your land. This passage is necessarily placed in close proximity to the passages describing warfare (as it is written: “When you go out in war…” [: 10]). As demonstrated in the Gibeonite War [Joshua 10: 27], the reason behind must not remain overnight is not the dignity of the corpse, but rather, the dignity of the land. In this respect it does not matter whether the dead body be Canaanite or Israelite.

AND THOU DEFILE NOT THY LAND. In the opinion of our Rabbis this is not merely a reason, meaning [that a corpse may not be left hanging] “in order that you defile not your Land,” for, if so, it would be permissible [to leave the dead overnight] outside the Land. Instead, this is a second negative commandment. Now, whoever leaves overnight the corpse of a criminal hanging, or of any dead body in the Land transgresses two negative commandments [his body shall not remain all night upon the tree, and thou defile not the Land] and a positive commandment [but thou shalt surely bury him the same day]. Outside the Land [whenever someone allows any corpse to remain overnight] he violates the positive commandment [mentioned] and the negative commandment [his body shall not remain all night] which is derived from the law of the hanging corpse, as I have explained. It is by reason of this negative commandment that Joshua buried the Canaanite kings during the day of their execution, although, in their hanging, there would not have been the curse which our Rabbis mentioned with regards to the blasphemer and idol-worshipper. Rather, it was on account of the uncleanness of the Land [which their hanging would have caused] or because he was apprehensive of the desecration of G-d on the basis of the parable of the two brothers, as I have mentioned.

כי קללת אלוקים תלוי, when passers by view the corpse of a person who has been hanged they are in the habit of cursing the judge who decreed this penalty, or the relatives of the victim curse the judges accusing them of handing down a harsh verdict for a “minor” offence, such as the collecting of kindling on the Sabbath. (Numbers 15,33) If the Torah considered it asr necessary to warn the people against cursing their judges, (אלוהים לא תקלל, Exodus 22,27) it did so because it is familiar with people’s psyches, more so than people themselves. Therefore, to counteract such violation of the law not to curse judges, לא תלין נבלתו, “his corpse is not to spend the night unburied,” but כי קבור תקברנו...ולא תטמא את אדמתך, “you must proceed forthwith to bury him, for as long as he stays unburied people may contract severe ritual impurity through contact with that body, or through being under the same roof as the corpse.”

כי קללת אלוהים תלוי, every disembodied creature is known as elohim; this includes the soul of human beings known as צלם אלוהים, “image of G’d.” [as He is without body, so this essence of a human being is without a body, does not need a body. Ed.] (Genesis 1,27) This is how we can understand the woman, known as בעלת אוב in Samuel I 28,13 whom King Sha-ul approached and asked to raise the prophet Samuel for him producing a disembodied image. Seeing that the disgrace done to a person after he has died is also an insult to this disembodied essence of him, the Torah describes it as קללת אלוהים, equivalent to cursing the dead person’s eternal essence. קללת אלהים, leaving the dead corpse hanging without burial is an insult to that very eternal essence of a human being called אלהים.

ולא תטמא, do not allow the spirit of impurity, death, to linger overnight in a location where a body remains unburied.

כי קללת אלוהים תלוי, “for an impaled body is an affront to G–d;” a body that has not been buried is as if one had cursed G–d, as anyone seeing that corpse will realise that the body while alive had cursed the Lord by his activities and tarnished the concept of man having been created in G–d’s image.