The uniqueness of the resurrection claim
One of the more compelling reasons for taking the early Christian resurrection claim seriously, in my opinion, is how different it was from analogous claims advanced by Jews and pagans around that time. There was a wide variety of concepts available in the ancient world to describe afterlife prospects, and stories were told of resuscitations, manifestations of spirits of the dead, the divinization of heroes, etc. There was even a kind of resurrection anticipated in ancient Egyptian religion, which implied a continued bodily existence in the underworld. The Jews around this time, of course, were expecting a general resurrection at the end of time which involved God raising human beings and the rest of creation to new life.
But the early Christian claim about what happened to Jesus was strikingly different. As Christopher Bryan says in his excellent new book, The Resurrection of the Messiah:
In speaking of their encounters with the risen Christ, the first Christians seem to have gone out of their way not to present them as experiences that could be understood as simply 'spiritual' or 'religious', as events purely internal or personal; nor did they speak of them in ways that might suggest they had received something-even if it were truly from God-that was entirely visionary or otherworldly, an annunciation or a theophany, like Gabriel appearing to Mary. In flat contradiction to all such views of what they might have seen or experienced, they claimed that the risen Jesus had eaten with his followers, had shown his wounds so that they might be touched, had been embraced, and had even cooked for them!...In this connection, two other Greek verbs that the first Christians persistently used in connection with their claims are striking. These are egeiro...and anistemi...As N.T. Wright has shown us, when the ancients, whether Jews or pagans, used these words or their cognates in connection with the dead, they seem invariably to have meant something like returning to a life that was at least in some measure continuous with previous life, after a period of being dead...They did not use these words to claim 'the immortality of the soul', nor did they associate them with experiences of the departed that were purely visionary or personal, or with coming to understand the real meaning of what had happened to someone, or with claiming that someone's teaching lived on even though they had died, or that God would eventually raise them in the age to come, or with anything of that kind. All these were ideas with which...different parts of the ancient world were perfectly familiar, and there is not the slightest reason to suppose that the first Christians would not have been able to articulate similar ideas about Jesus if they had wished to, or that anyone would necessarily have found such claims absurd if they had been made. But Jesus' followers did not do that. On the contrary, in one way or another, they seem consistently, and despite the obvious problem that it raised, to have talked about Jesus' having been 'raised from the dead'.Yet despite those elements-or perhaps we would better say, alongside those elements-the first Christian claims give us no grounds whatever to suppose that they thought that Jesus now came to them merely as he had been among them before...There are, as we have already noticed, examples of such resuscitation in the Jewish Scriptures, and there are also examples of it in the New Testament, notably, in the Gospels...In the New Testament as in the Old, such persons' restoration is invariably seen as an amazing miracle and a sign of God's power. But, also in the New Testament as in the Old, these are restorations to a life that is essentially still subject to the same weaknesses and limitations as it was before...a life that will still end in death [Note: I suspect that Herod's speculation that Jesus was actually John the Baptist come back from the dead falls in this category]Emphatically, and for all their material and this-worldly elements, this is not at all what the New Testament witnesses are talking about when they speak of the Risen Jesus. Quite clearly, the Risen Jesus is in a different category of life: indeed, he now possesses the life of God...These claims, moreover, do not merely mark the records of the evangelists, which at least in their present form are among the later New Testament statements. They mark the earliest among the New Testament assertions about him. Being raised from the dead he is "in power," as Paul puts it (Rom 1:4), or, as he says later in the same letter, "we know that Christ, being raised from the dead, will never die again; death no longer has dominion over him. The death he died, he died to sin, once for all; but the life he lives, he lives to God" (Rom 6:9-10)(Bryan, The Resurrection of the Messiah, pp.36-38)
To sum up, despite the bewildering variety of concepts available in the ancient world to describe afterlife prospects, none of them either in their more popular forms or in their weirder permutations, was adequate to describe what the early Christians claimed had happened to Jesus. The resurrection claims, whether in Paul, the other NT letters or the Gospels, are not hero divinization tales, nor manifestations of the departing spirit of Jesus, nor anything similar. They represent something strikingly new in religious history, and we should take very seriously the possibility that this uniqueness resulted from real experiences that shattered the disciples' expectations.