Christ was yet alive at this time, he had not become the sacrifice for sins yet. but unless he did the comforter would not come. who is the comforter? christ risen? the holy spirit? the father? there is a clue , john 16:13 Howbeit when he, the Spirit of truth, is come, he will guide you into all truth: for he shall not speak of himself; but whatsoever he shall hear, that shall he speak: and he will shew you things to come. " the spirit of truth was also mentioned in john 14:17 Even the Spirit of truth; whom the world cannot receive, because it seeth him not, neither knoweth him: but ye know him; for he dwelleth with you, and shall be in you
we know that when jesus said that ,jesus dwelt with them. he also said the spirit of truth shall be in you, that could be the father,jesus or the holy spirit. but it is certain that that christ knew that if he did not achieve what needed to be done , the sacrifice ,then the spirit of truth would not come. the holy spirit had come before,the WORD had come before, and the father,. apparently while he was in the form he was in something could not be done that needed to be done.