Thank you for biblical question, “Whoever is born of the flesh is flesh yet whoever is born of the Spirit is spirit (John 3:1-15). If the Son of God became flesh then how could He have returned to Heaven?”
John 3 speaks of the need of spiritual birth, not just a physical birth. Without a spiritual birth, no one can enter the kingdom of God.
Jesus states that no flesh can enter the kingdom of God since it is both physical and spiritual. The Apostle Paul states in I Corinthians 15 thee words, “I declare to you, brothers and sisters, that flesh and blood cannot inherit the kingdom of God, nor does the perishable inherit the imperishable.” (NIV).
At the resurrection of Jesus, Jesus’ body was not physical but also spiritual. Paul states this in the same chapter, “So will it be with the resurrection of the dead. The body that is sown is perishable, it is raised imperishable; 43 it is sown in dishonor, it is raised in glory; it is sown in weakness, it is raised in power; 44 it is sown a natural body, it is raised a spiritual body” (NIV).
Jesus was the firstborn of the resurrected dead who never died again. His body was raised an imperishable and spiritual body. Thus Jesus was able to enter into the house of the disciples without having to walk into the house and yet he can be touched or eat food. Jesus asked Thomas to touch his scars and wounds. There is a physical aspect to the resurrected body of Jesus but it is not limited to time and space. With a new physical-spiritual body, he is able to ascend to heaven or to descend to earth.
SUMMARY: The resurrected body of Jesus is both physical and spiritual without being limited to the natural laws of the Universe.
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