I would say it has a little more history to it than we credit it for. But still mostly theological. That is the position of N.T Wright. It just seems more theological as well. If we compare it to the Johannine epistles we can see this. A lot of the same poetic philosophical language is used. Also, there seems to be some external clues in some of the very early Church fathers that this was theological since there were problems with Gnostics at the time. For example, we find in Ignatius of Antioch Letter to the Smyrnaeans, "They abstain from the Eucharist and from prayer, because they confess not the Eucharist to be the flesh of our Saviour Jesus Christ, which suffered for our sins, and which the Father, of His goodness, raised up again. Those, therefore, who speak against this gift of God, incur death in the midst of their disputes. But it were better for them to treat it with respect, that they also might rise again. It is fitting, therefore, that you should keep aloof from such persons, and not to speak of them either in private or in public, but to give heed to the prophets, and above all, to the Gospel, in which the passion [of Christ] has been revealed to us, and the resurrection has been fully proved. But avoid all divisions, as the beginning of evils." We then find in John, which was written around the same time period as this, a long discourse by Jesus on the Eucharist in John chapter 6. And some of Jesus’s disciples desert him. The author was trying to make it clear in this chapter that the Eucharist is truly Jesus and that Jesus is truly human giving his flesh as food, but some of the so called followers of Jesus [Gnostics] deny this.