When is this the case? In a discretionary war; but in a war commanded [by the Torah] all must go forth —- even a groom from his chamber and a bride from her bridal chamber. R’ Yehudah said: When is this the case? In a war commanded [by the Torah]; but in a war of duty all go forth, even the groom from his chamber and the bride from her bridal chamber.

The [passage regarding the] decapitated calf [must be recited] in the Holy Tongue, as it is said (Deut. 21:1): If a corpse should be found, in the land ...  Your elders and your judges shall go out (ibid. 21:2) —- three [members] of the High Court in Jerusalem would go out. R’ Yehudah says: Five; as it is said, your elders —- two, and your judges —- [another] two, and [since] a court cannot be even, they add one more.

If it was found buried in a heap, or hanging from a tree, or floating upon the water, they would not decapitate [a calf]; as it is said: in the land (ibid. 21:1) —- [implying that it was] not buried in a heap; fallen —- but not hanging from a tree; in the field —- but not floating upon the water.  If it was found near the border, or near a city of which the majority are non-Jews, or near a city in which there is no court of law, they would not decapitate [a calf]. They do not measure except from a city in which there is a court of law.  If it was found equidistant from two cities, the two bring two calves; [these are] the words of R’ Eliezer.  Jerusalem is exempt from the rite of the decapitated calf.

If its head was found in one place and its body in another place, we bring the head to the body; [these are] the words of R’ Eliezer. R’ Akiva says: The body [is brought] to the head.