Since Christ was a Spiritual being at the time of His assertion, couldn't He have appeared in their mind, and disappeared when He ascended? They were the only ones to see Him, yes?
2 Kings 6:
15 And when the servant of the man of God was risen early, and gone forth, behold, an host compassed the city both with horses and chariots. And his servant said unto him, Alas, my master! how shall we do?
16 And he answered, Fear not: for they that
be with us
are more than they that
be with them.
17 And Elisha prayed, and said, LORD,
I pray thee, open his eyes, that he may see. And the LORD opened the eyes of the young man; and he saw: and, behold,
the mountain was full of horses and chariots of fire round about Elisha.
18 And when they came down to him, Elisha prayed unto the LORD, and said, Smite this people, I pray thee, with blindness. And he smote them with blindness according to the word of Elisha.
I believe God created our realm of "Time" and He lives in another realm all together that we can not see. A realm where "time" does not rule. Where there is no beginning or end. A concept our feeble minds will never be able to comprehend. So that all we know, and those things so far away we can't see them is just a globe or existence that God holds in His hands. The scriptures say there will come a time when there will be "TIME" no more. when some humans too will be allowed to "SEE" where He exists as they will become "like He is".
So for me His assentation has nothing to do with the physical earth, or planets of our existence. He manifested His Spiritual self to them is their mind, just as the servant of Elisha was allowed to see the protection God had afforded to Elisha.
Food for thought.