When Jesus told His disciples that He was leaving, and they would not be able to follow Him, they experienced sadness and hopelessness. They were bewildered and discouraged as well. John 7:34; 8:21; 12:8, 35; 13:33. He told them that He would die John 12:32-34. They had learned that one of them would betray Him. John 13:21. Peter would disown Him three times. John 13:38. Satan was at work against all of them. Luke 22:31-32. All the disciples would fall away Matthew 26:31. These revelations must have greatly depressed them.
Jesus comforted His disciples through several exhortations and promises. The first thing Jesus says to them is
Do not let your hearts be troubled.
The word “troubled” is tarassestho . It means “stirred, and agitated.” It comes from the same verb translated “troubled” in John 11:33; 13:21; 14:27. The heart is the center of one’s personality. Each believer is responsible for the condition of his heart. Compare Prov. 3:1, 3, 5; 4:23; 20:9. Through their trust in God the Father and Jesus the Son, they could relieve their deep sorrow and be sustained in their coming tests. Trust in God; trust also in Me is properly a command rather than a statement. Death should no longer be a terror to them. Jesus was leaving to prepare a place for them in Heaven–the Father’s house.
The fact that Jesus says He will come back means the Rapture of the church. Christ will return for His sheep. http://ref.ly/1Th4.13-18 They will be with Him. Look at the following verse:
John 17:24 (KJV)
(24) “Father, I will that they also, whom thou hast given me, be with me where I am; that they may behold my glory, which thou hast given me: for thou lovedst me before the foundation of the world.”
Notice the following references concerning this verse:
Throughout His ministry, Jesus had been showing them the way, but as Thomas indicated (John 14:5), they did not fully understand.