We were covering 1 Cor 15 in Sunday School this weekend. While the teacher skipped over this (among several other things, most notably the universalistic eschaton section in the middle ), I happened to see while paging around that there is apparently another translation option.
“Else what shall they be doing who are baptizing? It is for the sake of the dead absolutely if the dead are not being roused! Why are they baptizing also for their sake?” (Knoch’s Concordant Literal)
Other translations start and stop the sentences differently, so that the result would be (in parallel with the above way of putting it, and shifting the ‘absolutely’ somewhere else in the English grammar): “Else what shall they be doing who are baptizing for the sake of the dead? [Absolutely] if the dead are [absolutely] not being roused, why are they baptizing also for their sake?”
I haven’t had the wherewithal yet to compare this translation with the Greek to see how grammatically plausible it is; but it suggests that what Paul meant was that baptism at all is pointless if there is no resurrection to come. This would gel with Paul’s statement elsewhere that we are baptized into the death of Christ so that we might share in His life.