“Else what shal they do, which are baptized for the dead, if the dead rise not at all, why are they then baptized for the dead?”
1611 King James Version (KJV)
15:29 Who are baptized for the dead - Perhaps baptized in hope of blessings to be received after they are numbered with the dead. Or, baptized in the room of the dead - Of them that are just fallen in the cause of Christ: like soldiers who advance in the room of their companions that fell just before their face.
1Co 15:29 Else what shall they do who are baptized for the dead? Paul again returns to the argument for the resurrection. This passage is difficult, and has received almost as many interpretations as there have been commentators. Some have held that there was a custom of baptizing living persons for the benefit of persons who had died without baptism. Had that custom existed, Paul would have rebuked it. It did arise afterwards, as an abuse from the misinterpretation of this passage, among the followers of Cerinthis, and, in our times, of Joseph Smith. I will try to make clear its meaning: (1) All the Corinthians were baptized (Ac 18:8). (2) Their baptism was a "planting" in the likeness of the burial of Christ, and in the "likeness of his resurrection" (Ro 6:4,5). They were in, and raised from, a watery tomb. (3) Their baptism in the likeness of the death and resurrection of Christ was in hope of their own resurrection from the dead through Christ's resurrection. ("Huper Nekroon", "for", or "on account of the dead", with the exception of resurrection from the dead.) But if Christ has not risen, and the dead rise not, this memorial and emblematic burial has no meaning. "Why, then, are they baptized for the dead"? that is, for the sake of their own resurrection from the dead. This interpretation harmonizes better with Paul's argument than any I have seen.