Baptism is the outward manifestation of a new identification. This metaphorical understanding of baptism as a public identification is the only way to make sense out of some verses. Yesterday I dealt with Mark 16:16 and with 1 
Corinthians 10:1-2. Another verse that begs to be understood by the means of this metaphor is 1 Corinthians 15:29. This verse says: “Now if there is no resurrection, what will those do who are baptized for the dead?” There has always been some who have insisted on taking this verse literally and have been baptized for their ancestors or friends who have passed away thinking that this baptism on behalf of someone who had died will save their souls. This diametrically opposes too many biblical doctrines. I cannot accept this “literal” translation. But, if I allow Paul to use normal language and speak of Baptism metaphorically, it all comes together.
In that chapter Paul is arguing for the reality of the resurrection of the dead. He explains all the consequences if the resurrection of Christ was a hoax. But then brilliantly develops his argument and concludes his discussion in verse 20, with “But Christ has indeed been raised from the dead, the first fruits of those who have fallen asleep.” Because of Christ’s resurrection, the first fruits, we will make up the harvest as a whole to follow. He then addresses the absurdity of the Christian life if there is nothing awaiting us beyond the grave. If this is all there really is then we shouldn’t subject ourselves to ridicule, bodily discipline, persecution and even martyrdom at the hands of the unbelieving world. Identification with Christ brings its measure of that to every generation. However, if the resurrection is true, and there is indeed more to our existence than what meets the eye, we are more than willing to submit ourselves to the difficulties, hardships, sufferings of this life that result from our identification with Christ anticipating the great rewards in the life to follow.
If we put the idea of the believer’s identification with Christ in place of the literal term “baptism” in this verse, we might get what James M. Boice suggests. He says that verse might be translated like this (he attributes these thoughts to Donald Grey Barnhouse), “For what is the sense of being identified as dead men, if the dead rise not at all? Why should they be identified as dead? Why should they be crucified with Christ? And why are we standing in jeopardy every hour? Why are we in danger of persecution by the authorities for our way of life? I protest by your rejoicing which I have in Christ Jesus our Lord, I am identified with Christ in His death every day. That is, I am baptized every day. If after the manner of men I have fought with beasts at Ephesus, what does it get me, if the dead rise not? If there is no resurrection, then let us eat and drink, for tomorrow we shall be dead.” The whole context of Paul’s argument demands our understanding to be metaphorical. It’s the identification with the “death” of Christ which will be followed by “identification” of our resurrection with Christ.