Yes, Revelation implies “there was no longer any sea” (21:1). But many scholars believe this is alluding to the fact that the ancients, including the Jews, held the sea to be a habitation of evil. Of course evil is gone. But the earth cannot function without the oceans; they play a critical role in our water cycle, weather, and planet temperature. Besides—who can imagine a new earth without the glorious ocean? Perhaps more importantly, the Greek of Revelation 21:1 speaks of one world “passing away”