Was the resurrection physical, or just a spiritual vision?

No — the first Christians proclaimed a physical resurrection, though a transformed one. The objection rests on Paul's phrase "spiritual body" (Greek sōma pneumatikon, 1 Corinthians 15:44): the claim is that Paul meant Jesus rose in a new and different body, leaving the old one in the grave — so the tangible, empty-tomb stories were added later. But Paul taught that the risen body is the same body transformed, not a replacement.

On the most widely held reading "spiritual body" means not a ghost but a transformed physicality — a real, embodied body. Its precise force is debated: some take it to mean a body animated and governed by the Spirit, others a body of a refined heavenly substance — but on either reading Paul is describing a real, embodied risen Jesus, not a disembodied apparition. Paul uses the very same word of living people: the "spiritual person" of 1 Corinthians 2:15 is not a bodiless one. And his own seed analogy is about continuity through transformation, not replacement: what is sown and dies is what comes to life (15:36), and "this mortal body must put on immortality" (15:53) — this body, changed, not a different one issued in its place. He says it again elsewhere: Christ "will transform our lowly body to be like his glorious body" (Philippians 3:21).

Paul does teach that the risen body is radically changed — imperishable, glorious, powerful. What he never teaches is that it is a replacement, with the old corpse discarded. And in mainstream first-century Jewish usage, to call someone "raised" meant the body was raised; no one would describe a man as raised while his corpse still lay in the tomb. So Paul and the Gospels are describing one reality — a real, embodied risen Jesus, transformed but not replaced — and Paul's "spiritual body" gives no support to the idea that the first Christians proclaimed a risen Jesus over an occupied grave. (Whether the tomb was in fact found empty is argued on its own evidence.)