Sleep is a physical necessity for our earthly bodies. Without sleep, our brains stop working correctly, and our bodies refuse to cooperate. The sleep-wake cycle is just another of many cycles God has put into place on the earth -others include the cycle of changing seasons, day and night, and the water cycle. These cycles are part of life on this planet. However, the current heaven is in a different realm. Upon death, those who are “in Christ” will be immediately be with him (2 Corinthians 5:8) but will not yet have completely restored bodies. We must wait for the resurrection to receive those (1 Corinthians 15:40; 2 Corinthians 4:14; John 5:28-29)
Most people assume that Christians will “live forever in heaven” after they die, but that is not what scripture says. Heaven is in the spirit realm, beyond our universe, and earthly bodies are unequipped for existence there (1Corithians 15:50). Therefore, “sleeping” in heaven may even not be possible or necessary. Jesus described the temporary resting place for the righteous as being “near Abraham”. We will have some type of body, and will will recognize each other.We will have knowledge of the affairs on earth (Revelation 6:9-10). But we should take careful note of the reaction of human being who saw God in his glory as did Isaiah.
Living in the manifest presence of the Lord God Almighty will change everything. The things of earth, including sleep, will no longer have the same value to us.