John 1:13-15
Jesus Came from Heaven
13No one has ever gone into heaven except the one who came from heaven—the Son of Man. 14Just as Moses lifted up the snake in the desert, so the Son of Man must be lifted up, 15that everyone who believes in him may have eternal life.
John 14:1-3
Jesus to Prepare a Place for the Disciples
1 “Do not let your hearts be troubled. You believe in God; believe also in me. 2 My Father’s house has many rooms; if that were not so, would I have told you that I am going there to prepare a place for you? 3 And if I go and prepare a place for you, I will come back and take you to be with me that you also may be where I am.
Matthew 19:28-30
Jesus to Prepare a Place for His Disciples and Followers
28 Jesus said to them, “Truly I tell you, at the renewal of all things, when the Son of Man sits on his glorious throne, you who have followed me will also sit on twelve thrones, judging the twelve tribes of Israel. 29 And everyone who has left houses or brothers or sisters or father or mother or wife or children or fields for my sake will receive a hundred times as much and will inherit eternal life. 30 But many who are first will be last, and many who are last will be first.
If you take Jesus' statement He makes to Nicodemus literally, then the only One who has ever gone to heaven, up to point of time He was on earth was Him...Now maybe it is different now and after His ascension -and everyone that has been rightly judged, has already gone to heaven back to His and our Father...We are not told when the renewal of all things will be or was (it maybe at our deaths or when Jesus separates the sin from and out of us), or even exactly what if means...But Jesus, will be on His Glorious Throne and the Disciples will be there with Him in heaven...
These things are hard to understand, because we know little about heaven...The knowledge we get about heaven, is from the words Jesus has given us about heaven...He is the Only One who has came from heaven, and back to earth... But heaven is a specific place, and Jesus is there...He prepares a room (there in heaven) for those who get to heaven...And those who have followed and believed in Him, will be there with Him...I suspect, just being there with Him and His Father and being is Their Presence, is what makes heaven, heaven...