"... No early source directly links this final purification of the deceased with the resurrection. Yet, because belief in the resurrection became increasingly wide-spread among Jews in the Second Temple, one may reasonably suppose that acts honoring the dead, including purifying them for burial, were understood to be related to resurrection. That would certainly agree with the Maccabean literature then in circulation that highlighted Jewish hero Judah Maccabee's belief in the resurrection, and his actions to ensure the atonement of dead companions (2 Maccabees 12:43–45) ... Jews of the Second Temple certainly did perform a purification washing for the benefit of their deceased. There is good reason to suppose that many Jews associated the practice with the resurrection, and this conforms well with Paul's remark in 1 Cor. 15:29. Conversely, the Greek denial of resurrection seems to preclude Paul's remark from any association with Greek funerary washings ..."

"... 2 Maccabees 12:43-45 is especially interesting since it supports the resurrection belief based on the actions taken by Judas’ act and his troops upon realizing that their brothers in arms had fallen in the battle due to “the sacred tokens of the idols of Jamnia” worn under their tunics (verse 40). Jonathan Goldstien noted that Jason engages “in a complicated piece of logical gymnastics to prove that Judas believed in the resurrection of the dead”. Jason argues that Judas’ act of collecting two thousand drachmas of silver to provide for a sin offering and prayers on behalf of the dead soldiers would have been foolish and superfluous unless he was expecting that this deed would somehow be helpful and bring atonement for the sin they had committed. From this, Jason concludes, Judas’ intent was to expiate for their grievous acts of idolatry so they would be able to partake in the resurrection of the righteous and receive the splendid reward awaiting them (verses 44-45). It should be noted that Paul uses the same “logical gymnastics” when arguing for a resurrection belief in 1 Corinthians 15:29 based on the practice of baptizing a person on behalf of the dead ..."

"... The major problem in this passage is the interpretation of “those who undergo baptism on behalf of the dead,” or “in place of the dead” in verse 29. The Corinthian practice to which Paul is alluding is mentioned only here, and not with sufficient clarity to understand precisely what the nature of the practice was. Consequently, the number of explanations of vv. 29–30 that have been proposed are legion. DeMaris has done well to situate the problem in what is known from archaeology and ancient anthropology about concern for the dead and the passage from life to death among contemporary Greeks and Romans, especially at Isthmia and in Corinthia as the centers where the cults of Palaimon and Demeter developed (“Corinthian Religion”). Such a concern about the afterlife and the underworld among Corinthians might explain why Christians who lived there developed their own practice of showing concern for the dead, whatever explanation is found best suited for “baptism on behalf of the dead” ... Marmorstein also relates to this passage the episode in 2 Maccabees 12:39–45, where Judas Maccabee provides an expiatory sacrifice in Jerusalem for those slain “inasmuch as he had the resurrection of the dead in view” ..."