Paul, an apostle, not from men, neither by man, but by Jesus Christ, who raised him from the dead
As I have noted many times here, no one seriously believes that the apostle wrote these words himself. These were fixed by the early editor of the canon so readers would know the identity of the author. In this case, with the Marcionite omission of the words 'by God the Father' there is only sensible reading is clearly that Jesus raised his spokesman Paul from the dead.
There are a number of wonderful studies of the Marcionite reading of the text - Baarda's recent effort stands out among this group. Yet none have taken the obvious connection that the reference here is clearly to the resurrection of the youth in the gospel which preceded the Apostolikon collection - i.e. to 'Secret Mark.' I have always thought that the Alexandrian text of Mark is clearly the Marcionite gospel already alluded to being 'according to Mark' in Philosophumena Book Seven. Yet for those who have not been following my arguments let's consider the alternatives by going through a number of references to the 'resurrection of the dead' and 'the resurrection of Christ' in the Apostolikon and see whether the claim of many (Baarda included) that the superscription in Galatians should be read 'Jesus raised himself from the dead' (i.e. rather than a separate individual who was this God's 'Christ').
The most famous discussion of the resurrection of the dead of course appears at the conclusion of what we have learned to refer to as 1 Corinthians. In order for the Marcionite claim that Jesus simply 'raised himself' from the dead we'd have to explain this reference cited by Tertullian in Book Five of his anti-Marcionite treatise:
“For,” he says, “since by man came death, by man came also the resurrection of the dead.” (This he says) in order, on the one hand, to distinguish the two authors — Adam of death, Christ of resurrection. [Against Marcion 5.9]
Of course we have an inherited an understanding that 'Christ' here is also 'the God' Jesus (= the Lord). Yet the Marcionites are repeatedly identified as holding that Jesus was only God. In other words, the Marcionites explicitly denied Jesus's humanity. As such, the 'Christ' who is explicitly being referenced as 'man' in 1 Corinthians 15 can't also be the God Jesus. Jerome goes out of his way to say that the Marcionites denied any humanity to Jesus.
A little later Tertullian notes that the resurrection of Christ is also linked by the apostle to his baptism or quite specifically - the baptism for the dead. We read:
What, he asks, shall they do who are baptized for the dead, if the dead rise not? That practice must speak for itself. Perhaps the kalends of February will answer him: pray for the dead. Abstain then from at once blaming the apostle as either having recently invented this or given it his approval, with intent to establish the resurrection of the flesh more firmly in that those who without any effect were having themselves baptized for the dead were doing so by faith in the resurrection.
I am not interested in taking much time to attack or support Tertullian's explanation of what the terminology here means with respect to the 'baptism for the dead.' Our only point is to note again that the Marcionite interpretation of these words could not have imagined that the god Jesus was the original 'man' who died, resurrected and baptized. 'Christ' for the Marcionites had to have been a man who underwent all these things by means of the power of the wholly divine Jesus.
So again the same logic applies to the passage which follows a little later where Tertullian notes:
For restitution of an object is only made to him who has lost it, and so it can be a resurrection of the dead only so long as it is a resurrection of bodies. For he proceeds: He that raised up Christ from the dead shall also quicken your mortal bodies. In this way he confirms the resurrection of the flesh, since apart from flesh nothing else can be described as body, nor anything else be taken for mortal: and he has also given proof of Christ's corporal substance, in that our mortal bodies are to be quickened on the same terms on which he too was raised up again, and on the same terms can only mean in the body. [Against Marcion 5.14]
Again I leave to the side the whole question of Tertullian's interest in proving that Jesus had to have had a material body because the resurrection necessarily required it. He attempts to paint the Marcionites into a corner in this respect and scholars are all too willing to go along with him. Nevertheless, the obvious solution again is that Jesus the God was never understood by the Marcionites to have underwent resurrection at all.
Just look again at the original reference here from the Apostolikon namely:
He that raised up Christ from the dead shall also quicken your mortal bodies.
Clearly the Marcionites couldn't have understood the 'he' here to mean the dead Christ who needs raising - i.e. Christ that raised up Christ from the dead shall also quicken your mortal bodies.' The only possible solution again is that the sentence read:
Jesus that raised up Christ from the dead shall also quicken your mortal bodies.
Indeed as we have already seen the Marcionite obviously held that their apostle was Christ. The consistent use of the active voice to speak of God's raising Christ (cf. Rom. 8:11) was clearly understood by the Marcionites to mean 'another person beside Jesus' in the same way they read many of the gospel parallels in this manner.
