Question on Luke 24:36-43

[living]

I got a question while reading the following passage and thought to bring it on here.

Recall the occasion when Jesus returned to that upper room after the crucifixion:

Luke 24:36-43
"..Jesus himself stood in their midst, and said unto them, Peace be unto you...But they were terrified, and supposing that they were seeing a spirit... And he said unto them,.. 'Behold my hands and my feet, that it is I myself: handle me and see; for a spirit has no flesh and bones, as you see me have'... And showed them his hands and feet... And while they yet believed not for joy and wondered, he said unto them, 'Have ye here any meat?'.. And they gave him a piece of broiled fish, and of a honeycomb... And he took it, and did eat before them."

Now the question:
Why should they be terrified? When one recognizes one's long-lost friend or one's beloved, the natural reaction is to feel overjoyed, elated and one wants to embrace and kiss the hands and feet of the beloved. Why did they get terrified?
Did Jesus look like a Spiritualized body (a ghost)?

 

[Boanerges]

Though Jesus taught them much they had no ears to hear before the day of Pentecost and thought they were seeing a ghost. They were apparently fairly superstitious as they had done the same thing (cowered in fear) when they saw Jesus walk on the water, again thinking Him a ghost.
These men were already scared hiding behind locked doors and expecting the Jewish counsel and/or Romans to come for them. Cowering in fear for their lives to fearless lions for Christ. What a stark transformation but this would not occur until the Holy Spirit fell on them.