John Chrysostom — as excerpted in the Catena Aurea on John 14:18-21

“(Hom. lxxv. 1) At the first He said, Whither I go ye shall come; but as this was a long time off, He promises them the Spirit in the interval. And as they knew not what that was, He promises them that they most desired, His own presence, I will come to you: but intimates at the same time that they are not to look for the same kind of presence over again: Yet a little while, and the world seeth Me no more: as if He said, I will come to you, but not to live with you every day as I did before. And, I will come to you alone, He says, thus preventing any inconsistency with what He had said to the Jews: Henceforth ye shall not see Me.”