Serious answers only.Jesus was a friendly Spirit so why were His friends afraid?

[Aoiffe337]

According to Acts, Jesus entered the Upper Room where His friends were assembled. They were afraid; and He identified Himself,admonishing them to not fear.Didn't they recognize Him? Is it natural to be afraid of spirits? How do you know if the spirit is evil or sent by God if it creates fear? Mary was afraid in the presence of Gabriel. Peter was afraid when Jesus walked on the water.

[Joanie Pony]

In there I think you have already come to a conclusions.There are many interpretations of the bible,what version are you quoting from/.

[retroactivism]

Maybe the were afraid because they thought he was dead.

[Bryan]

Because they didn't believe that Jesus would come back. And think of it this way, if a spirit (doesn't matter good or bad) confronted you would you be scared.

[Edward H]

I know that if I were in the presence of Jesus bodily, I too would have a REVERENT fear of the awesomeness of HIM being in front of me. To think that HE knows all the thoughts and intents of my heart is quite a fearful thought.
Peter was not afraid of Jesus walking on the water, Peter took his eyes off Jesus when he stepped out of the boat onto the water and it was Peters fear of drowning that caused him go under.
Matthew 14:28-30 (King James Version)
King James Version (KJV)

28And Peter answered him and said, Lord, if it be thou, bid me come unto thee on the water.
29And he said, Come. And when Peter was come down out of the ship, he walked on the water, to go to Jesus.

30But when he saw the wind boisterous, HE WAS AFRAID; and beginning to sink, he cried, saying, Lord, save me.

[benjamingin]

Because he was sent by God. People naturally fear God.

[LTD]

In any point in history, even modern day times, seeing someone walk on water would freak you out...doncha think?
Fear comes from not understanding something...once something is understood, fear goes away...