Read 1 Corinthians 15:29 Using Other Translations
Else what shall they do which are baptized for the dead, if the dead rise not at all? why are they then baptized for the dead?
Otherwise, what do people mean by being baptized on behalf of the dead? If the dead are not raised at all, why are people baptized on their behalf?
If the dead will not be raised, what point is there in people being baptized for those who are dead? Why do it unless the dead will someday rise again?