Originally Posted by Poimen

Robert:

"The dead" in 1 Corinthians 15:29 is in the genitive case which rules out the second meaning. The second meaning 'above' or 'superior' would only apply if the the noun was in the accusative.

As to your first question, A.T. Robertson states that there are 30 different interpretations for this verse. So I hesitate to offer a definitive answer. I would state however:

1) The spiritual interpretation may take in to consideration the larger context and teaching of the NT, but ignores Paul's basic point in the immediate context: physical death - vs. 26 & 32. It seems clear that he is saying that some are baptized for those who have already passed on (the real 'crisis' he addresses in the passage vs. 12ff).

2) We don't have enough historical/geographical information to properly explain what some in the Corinthian church were doing as they 'baptized for the dead'.

3) Whatever it might mean, Paul does not actually command them to do so. In other words, there is no indication that this is normative for the NT church only that Paul says their current practice contradicts the statement of some who deny the bodily resurrection.

Indeed baptism for the (physically) dead is neither commanded or even implied in any major baptismal text. Furthermore, there is no basis for the Mormon understanding of this verse other than the traditions which they have invented.