What did Paul mean when he spoke of being “baptized for the dead” (1 Corinthians 15:29)?

Some among the Corinthians were claiming that there is no resurrection from the dead. As part of his response, Paul asks, “Otherwise, what will they do who are baptized for the dead, if the dead do not rise at all? Why then are they baptized for the dead?” (1 Corinthians 15:29).

Expositors have offered numerous interpretations of the unusual words “baptized for the dead.” Some have argued that this phrase could be translated “baptized in view of the dead,” which would roughly coincide with the baptismal portrait of the burial of the spiritually dead “old man” and the raising to life of the “new man in Christ.” Others claim that the strange expression refers to new members being baptized to replace members who have died. However, these explanations lack solid textual support.

The most likely interpretation is that some among the Corinthian heretics were being baptized on behalf of deceased loved ones who had not received baptism during their lifetimes. Paul does not condone the practice; he merely notes the fact that some were doing it. His point is that if they do not believe in the resurrection of the dead, then it makes no sense for some of their number to practice baptism for the dead.