NOTES for Luk 24:36-38
The apostles' reaction to the risen Jesus appearing among them is entirely understandable if one allows that at that time they still knew about the Kingdom and its life more by hearsay than from their own experience. It could not have been otherwise: the experience of the life of the Kingdom began to open to them on the day of Pentecost, which still lay ahead of them. For now, they remained completely inhabitants of this world, knowing about death and the afterlife no more than any of their contemporaries knew about them.
People in those days connected the afterlife with the world of shadows, with the realm of the dead, where everyone goes and where there is no question of any recompense. There were, of course, other versions, among the Egyptians, for example, or among the Greeks, who taught both about different states of postmortem existence and about postmortem recompense, but they were not very widespread and usually did not go beyond the cultural and religious tradition within which they had been formed.
Among the Jews there was no developed teaching about the afterlife, and Yahwist ideas about it did not differ from the ideas of most other peoples. So what could the disciples have thought when they saw their living Teacher before them? Their first thought was: this is a ghost, a shadow that has come out of the tomb. The corresponding Greek word here can mean both "breath" and "spirit" in the sense of the Spirit of God, but also "spirit" in the sense of a shadow, ghost, or apparition.
In Sheol, as the realm of the dead is called in Hebrew, there could be nothing but shadows, ghosts, and spirits. Sheol is not simply a place of death; it is a place of unceasing dying that can never come to an end. The biblical understanding of the soul sees in it a stream of life that can be more or less full depending on how much of God, His presence, and His breath there is in a person's life. This stream can be utterly full, as is the life of the Kingdom, or it can barely trickle, almost dried up, as is the existence of shadows in Sheol.
In the Kingdom, life overflows like wine from a cup during Shabbat; in Sheol, a person feverishly tries to hold on to the pitiful remnants of it that he managed to carry with him from the world of the living. In the fallen world before the coming of Christ, Sheol was the only real afterlife. People spoke of the resurrection, waited for it, and believed in it, but no one truly knew what it would be like. And so they take the risen Savior for a shadow that has come out of the tomb, only to be convinced very soon that in reality He is far more alive than anyone who considers himself alive.