Lucy, you are correct that those who have died in Christ from the beginning of the church until now, are in heaven, but in their spirits. The word anastasis translated as resurrection, is defined as a bodily standing up again. It specifically has to do with the physical body. Therefore, for those believers who are in their spirits in heaven, they need to and are waiting for the resurrection of their bodies, just like Jesus. Paul said, "I have the same hope as these men, that there will be a resurrection of both righteous and the wicked. The resurrection is when the spirit returns to the body and stands up again. The word anastasis never refers to a spiritual resurrection, because it is in contradiction to the definition of the word.
You are correct, the apostles and first century Christians, as well as every believer since that time. However, when their bodies died, their spirits departed and went to heaven, not their bodies. This is what the resurrection is all about. Rising again! Consider the following definition of the word anastasis translated as Resurrection:
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Strong's Concordance
anastasis:
a standing up, i.e. a resurrection, a raising up, rising
Original Word: ἀνάστασις, εως, ἡ
Part of Speech: Noun, Feminine
Transliteration: anastasis
Phonetic Spelling: (an-as'-tas-is)
Definition: a standing up, a resurrection, a raising up, rising
Usage: a rising again, resurrection.
HELPS Word-studies
386 anástasis (from
303 /aná, "up, again" and
2476 /hístēmi, "to stand") – literally, "stand up" (or "stand again"),
referring to physical resurrection (of the body).
Christ's
physical resurrection is the foundation of Christianity, which also guarantees the future resurrection of all believers (see Jn 6:39,40,44).
[
386 /anástasis ("resurrection") r
efers to the physical, bodily resurrection of Christ – and people (both of the redeemed and the unredeemed).]
Consider what Paul said regarding those who people of faith who are currently in heaven, in their spirits:
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By faith the walls of Jericho fell, after the people had marched around them for seven days.
31By faith the prostitute Rahab, because she welcomed the spies in peace, did not perish with those who were disobedient.
32And what more shall I say? Time will not allow me to tell of Gideon, Barak, Samson, Jephthah, David, Samuel, and the prophets,
33who through faith conquered kingdoms, administered justice, and gained what was promised; who shut the mouths of lions,
34quenched the raging fire, and escaped the edge of the sword; who gained strength from weakness, became mighty in battle, and put foreign armies to flight.
35Women received back their dead, raised to life again. Others were tortured and refused their release, so that they might gain a better resurrection.
36Still others endured mocking and flogging, and even chains and imprisonment.
37They were stoned, they were sawed in two,
f they were put to death by the sword. They went around in sheepskins and goatskins, destitute, oppressed, and mistreated.
38The world was not worthy of them. They wandered in deserts and mountains, and hid in caves and holes in the ground.
39These were all commended for their faith, yet they did not receive what was promised.
40God had planned something better for us, so that together with us they would be made perfect.
Therefore, since we are surrounded by such a great cloud of witnesses, let us throw off every encumbrance and the sin that so easily entangles, and let us run with endurance the race set out for us.
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