Since Mormonism claims to be the restoration of the ancient Christian Church which was somehow taken from the earth (despite Christ's promise that it would not be defeated), it behooves us all to look yet again at what the early Church actually said when it came to these verses, and whether or not they took them to be endorsing the practice of baptizing dead people (either by proxy as Mormons do, or in any other way).
Spoiler alert: the answer is no. That's why no Christian church does so today. It's a practice of heretics of the past, which Christians know better than to follow or continue.
From his
40th homily on 1 Corinthians, St. John Chrysostom (d. 407) observes, regarding the phrase "baptized for the dead" and how some people ran with it:
What then is that which he means? Or will you that I should first mention how they who are infected with the Marcionite heresy pervert this expression? And I know indeed that I shall excite much laughter; nevertheless, even on this account most of all I will mention it that you may the more completely avoid this disease: viz., when any Catechumen departs among them, having concealed the living man under the couch of the dead, they approach the corpse and talk with him, and ask him if he wishes to receive baptism; then when he makes no answer, he that is concealed underneath says in his stead that of course he should wish to be baptized; and so they baptize him instead of the departed, like men jesting upon the stage. So great power has the devil over the souls of careless sinners. Then being called to account, they allege this expression, saying that even the Apostle has said,
"They who are baptized for the dead." Do you see their extreme ridiculousness?
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And regarding its true meaning, the great saint instructs:
But first I wish to remind you who are initiated of the response , which on that evening they who introduce you to the mysteries bid you make; and then I will also explain the saying of Paul: so this likewise will be clearer to you; we after all the other things adding this which Paul now says. And I desire indeed expressly to utter it, but I dare not on account of the uninitiated; for these add a difficulty to our exposition, compelling us either not to speak clearly or to declare unto them the ineffable mysteries. Nevertheless, as I may be able, I will speak as through a veil.
As thus: after the enunciation of those mystical and fearful words, and the awful rules of the doctrines which have come down from heaven, this also we add at the end when we are about to baptize, bidding them say, I believe in the resurrection of the dead, and upon this faith we are baptized. For after we have confessed this together with the rest, then at last are we let down into the fountain of those sacred streams. This therefore Paul recalling to their minds said,
"if there be no resurrection, why are you then baptized for the dead ?" i.e., the dead bodies. For in fact with a view to this are you baptized, the resurrection of your dead body, believing that it no longer remains dead. And thou indeed in the words makest mention of a resurrection of the dead; but the priest, as in a kind of image, signifies to you by very deed the things which you have believed and confessed in words. When without a sign you believe, then he gives you the sign also; when you have done your own part, then also does God fully assure you. How and in what manner? By the water. For the being baptized and immersed and then emerging, is a symbol of the descent into Hades and return thence. Wherefore also Paul calls baptism a burial, saying,
"Therefore we are buried with Him by baptism into death." (Romans 6:4) By this he makes that also which is to come credible, I mean, the resurrection of our bodies. For the blotting out sins is a much greater thing than the raising up of a body. And this Christ declaring, said,
"For whether is easier to say, Your sins are forgiven, or to say, Take up your bed, and walk?" (Matthew 9:5)
"The former is the more difficult," says He,
"but since you disbelieve it as being hidden, and make the easier instead of the more difficult the demonstration of my power, neither will I refuse to afford you this proof." Then says He to the paralytic,
"Arise, take up your bed, and go unto your house."
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This is the proper understanding, and there is no other in the historical Christian church, nor in those who claim descent from it with any degree of historical backing, and I can say this with a high degree of confidence that does not rely on one man only (St. John Chrysostom just happens to be the only one I know that has been translated to English who contrasts the true teaching with the practices of those who do not interpret it correctly, so his words are closest to our situation when talking to Mormons about how this belief and practice is wrong), in light of the fact that there are Eastern Orthodox, Roman Catholic, and Oriental Orthodox posters posting here, and we all -- together with our Protestant friends -- agree that the Mormon practice and justification is absolutely bankrupt and without merit, and contrary to what we actually find when we look for evidence either for or against Mormon claims in the actual preserved writings of the early Christian church.
It's not a part of Christianity, and never has been. It's at best a part of various Gnostic sects which are so incredibly bizarre and off-base that St. John the Golden-Mouthed basically says that they are
laughable. Consider that: apparently this understanding that led to baptizing actual dead people was so obviously wrong to the early Church that they would laugh about it. While I would have a hard time laughing at Mormonism's practice (because I don't think it's funny that millions of people are deceived into following Gnosticism under the guise of 'restored' Christianity), I can definitely see why the people who did this stuff were objects of ridicule for early Christians. It is almost like a parody by inversion of what the actual Christian Church does.
