In 1 Corinthians 15 the Apostle Paul engages a fairly fundamental problem in the church in Corinth: some of the Christians are saying that there is no resurrection of the dead. It appears they are not questioning the resurrection of Christ, because Paul's counter-argument is to point out that if there is no resurrection of the dead then Christ himself is not raised. And if Christ is not raised, the apostolic preaching is a lie, and the faith of the Corinthian Christians is a sham.
For Paul's argument to work, the Corinthian Christians have to accept the resurrection of Jesus. So what are they denying? Presumably they are denying what might be called the general resurrection. Although Christ was raised, they do not expect themselves to be raised, at least not bodily. Bodily resurrection would have been distasteful to Hellenistic culture anyway. So Paul's argument is: if no general resurrection - if no last day on which all are raised, to life or judgement - then no particular resurrection of Christ; but Christ is raised, therefore we look to the resurrection of all.
Apologetically, Paul makes it clear that everything hinges on the fact that Christ is raised from the dead, and the evidence for this is the testimony of the many who saw him alive (including 500 at once, most of whom are still alive when Paul is writing, and can therefore be consulted; also, of course, including Paul himself).
What particularly strikes me today about this passage is what Paul assumes the resurrection of Christ to be. What does he think has happened?
Paul believed in and looked for the resurrection of the dead before he ever met Jesus. Like Martha, he expected the resurrection of the just at the last day. This was part of his Jewish heritage, part of the Scriptural testimony which he had absorbed from youth. Paul didn't need the resurrection of Jesus to persuade him of the general resurrection.
But also like Martha, Paul has been brought face-to-face with the fact that Jesus is the resurrection. The last day - the resurrection of the just - has in some sense already come. Christ is the first of all those who will rise. That is why Paul says that if there is no (general) resurrection then Christ himself has not been raised. The resurrection of Jesus is the general resurrection. In him, the future hope of a faithful Jew like Paul has been brought into the present. The age to come, quite simply, has come.
That is not to say that the age to come is not still in the future. Christ is the firstfruits, and the guarantee that the rest will follow. But something truly dramatic has happened in the resurrection of Christ. In our individualistic way, we tend to think of the resurrection of Jesus as one thing, and my resurrection to come as another. But for Paul, the future resurrection of all is so closely linked to the resurrection of Christ that one without the other is unthinkable. They are in principle the same event, the general resurrection so wrapped up in the person of Christ that they can't be separated.
It's a new day. He is risen, we will rise.
Soar we now where Christ has led, Alleluia!
Following our exalted Head, Alleluia!
Made like him, like him we rise, Alleluia!
Ours the cross, the grave, the skies, Alleluia!