NOTES for Luk 24:36-38
The apostles' reaction to the appearance among them of the risen Jesus is entirely understandable if we allow that 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 still remained quite fully inhabitants of this world, knowing about death and the afterlife as much as any of their contemporaries knew.
People in those days associated the afterlife with the world of shadows, the realm of the dead, where everyone goes and where there is no question of any recompense. There were, true, other variants, among the Egyptians, for example, or among the Greeks, who taught about different states of postmortem existence and about recompense after death, but these were not very widespread and usually did not go beyond the cultural and religious tradition within which they had taken shape.
Among the Jews there was no developed teaching on the afterlife; Yahwist ideas about it did not differ from the ideas of most other peoples. So what could the disciples think when they saw the 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 shade, ghost, or apparition.
In Sheol, as the realm of the dead is called in Hebrew, there could be nothing but shadows, ghosts, spirits. Sheol is not simply a place of death; it is a place of unceasing dying that cannot come to an end. The biblical idea of the soul sees in it a stream of life that can be more or less full depending on how much God, His presence, and His breath are in a person's life. This stream can be supremely full, such is the life of the Kingdom, or it can barely trickle, almost dried up, such is the existence of shadows in Sheol.
In the Kingdom life overflows like wine from a cup during the Sabbath; in Sheol a person feverishly tries to hold on to the pitiful remnants of life that he managed to carry with him from the world of the living. In the fallen world before Christ's coming, Sheol was the only real afterlife. People spoke of resurrection, waited for it, believed in it, but no one truly knew what it would be. So the risen Savior too is taken for a shadow that has come out of the tomb, only for them very soon to be convinced that in reality He is far more alive than anyone who considers himself alive.