When witnesses come to testify that a person has died, it is obvious that they must be certain that they saw that person dead. Thus, the Mishna on our daf rules that even if the witnesses saw someone being crucified or being mauled by a wild animal, they cannot testify unless they are sure that he was killed.
Crucifixion was one of the methods of capital punishment used by the Romans during Mishnaic times. This cruel and unusual punishment was usually carried out on slaves and individuals captured during times of rebellion. The crucifixion itself did not kill the prisoner, as what was done was simply nailing the person’s hands and legs on a wooden cross. Death usually was the result of dehydration and loss of blood, which is why, on occasion, people who were nailed to a cross were taken down and survived.
With reference to the ruling in our Mishna, the Talmud Yerushalmi comments that we can never be sure that someone who was known to have been crucified was dead. Given the length of time that a person could be on the cross before he died, during that time a Roman matron may come by and request that he be taken down, or else appeals could be made to the authorities for clemency. Josephus writes that on several occasions when he chanced across acquaintances who were being crucified he successfully arranged to have them taken down from the cross and they survived.
With regard to the Mishna’s ruling that even seeing a wild animal eating away at a person is not enough to testify to his death, the Talmud Yerushalmi suggests that we must assume that the Heavens showed mercy on him and that the animal abandoned him without killing him. Nevertheless, in our Gemara Rav Yehuda quotes Shmuel as ruling that this is only the case if the animal is not attacking one of his vital organs. If the animal is eating a part of the man’s body that would kill him, then we can accept such testimony.