Many use the following verse to prove that good people go to heaven the moment they die;
Luke 23: And Jesus said unto him, Verily I say unto thee, To day shalt thou be with me in paradise.
But since we know that not even Jesus Himself went to heaven to be accepted by the Father at the time of His death, how is it possible the thief went? It's not! And since it's not that MUST mean Jesus was talking about a time in the future for the thief to receive the promise that Jesus made to him.
These same people then say, "Well what about Moses and Elijah appearing with Jesus on the mountain?"
Well, let's read what Paul had to say about some of the saints that died. Let's read if they have received the promise of eternal life with christ yet.
 By faith Moses, when he was born, was hid three months of his parents, because they saw he was a proper child; and they were not afraid of the king's commandment.
 By faith Moses, when he was come to years, refused to be called the son of Pharaoh's daughter;
 Choosing rather to suffer affliction with the people of God, than to enjoy the pleasures of sin for a season;
 Through faith he kept the passover, and the sprinkling of blood, lest he that destroyed the firstborn should touch them.
 By faith they passed through the Red sea as by dry land: which the Egyptians assaying to do were drowned.
and the following;
 And what shall I more say? for the time would fail me to tell of Gedeon, and of Barak, and of Samson, and of Jephthae; of David also, and Samuel, and of the prophets:
So the above would include Elijah. Now let's read if any of these have received the promise of eternal ilfe with Christ;
 And these all, having obtained a good report through faith, received not the promise:
 God having provided some better thing for us, that they without us should not be made perfect.
So Moses, Elijah or any of the saints are in God's kingdom. They have not received their spirit bodies. Let's read when this will happen. Let's read when they will become perfect;
 So also is the resurrection of the dead. It is sown in corruption; it is raised in incorruption:
 It is sown in dishonour; it is raised in glory: it is sown in weakness; it is raised in power:
 It is sown a natural body; it is raised a spiritual body. There is a natural body, and there is a spiritual body.
Notice these bodies will be RAISED! And at what time? Let's read;
 Behold, I shew you a mystery; We shall not all sleep, but we shall all be changed,
 In a moment, in the twinkling of an eye, at the last trump: for the trumpet shall sound, and the dead shall be raised incorruptible, and we shall be changed.
 For this corruptible must put on incorruption, and this mortal must put on immortality.
So the thief, Moses, Elijah, Abraham, David, and ALL those saints that died with a good report, and those alive at Jesus return, will all receive God's promise at the same time!
At the LAST trump! That's when the saints of God will receive the promise. And not a moment sooner!
As a side note: Even after receiving the promise NO ONE is still going to heaven!