Revelation 21:1

Heaven is God's dwelling place. The new earth is not one of rocks, trees, etc., since, as McCord notes, we will have spiritual bodies for a spiritual existence. (1 Corinthians 15:44-50) God is a spirit with no flesh and bones. (John 4:24; Luke 24:39) Jesus became flesh to dwell on earth but has now returned to a spiritual existence. (John 1:14; 2 Corinthians 5:16) We know we will be like him when he receives us unto glory. (1 John 3:2) So, we can say the new earth is a place for spiritual beings. The old heaven and earth will pass away, as other passages also teach. (Hebrews 12:25-28; 2 Peter 3:10) The sea, in other parts of the earth, has stood for the restless masses of humanity. Coffman says some suggest the sea separated John from his beloved brethren in Asia Minor and now the separation was over. In either case, some troubling barrier has been removed and that is a beautiful thought.