Jesus made the statement to his disciples in John 14:11 " Believe me when I say that I am in the Father and the Father is in me; or at least believe on the evidence of the works themselves." HIs disciples who had spent three and a half years with him were being told He was going away. What a change was going to be happening in their lives. They were so comfortable with having Him walk with them, eat with them, teach them daily. Why would he leave now? How could Jehovah God, the Father be as trustworthy as Jesus? Jesus was God incarnate and in his leaving, He was going to give them something even better than His physical presence.