Early on in our study of Revelation I said the images we would read about are important. They are taken from a Jewish "Image-Pool" and are reflective of John's perspective about life, his personal situation and God's desire to tell John all will be good in the midst of the suffering of John and John's people. This situational perspective that God projects into John's mind is highlighted by the very first sentence of Revelation 21. Here are a few of the things going on.
First, let's understand that John is in exile on Patmos. He cannot come and go as he pleases. In fact, he is under arrest and the island is his prison cell. I am sure john desires to be free to preach and teach about the God he has come to trust for daily bread and for daily connection. So in the very first sentence God tells John the new heaven and the new earth has no sea. The barrier (the sea) that is there every day will be gone when God creates "all things new."
Second, in Jewish imagery the sea is the realm of evil things like ghosts, spirits and a myriad of things that will do people harm. God also removes this evil, making sure John knows that God has eradicated all evil from the heaven of our eternal dwelling.
Finally, God accentuates (over and over) that what He is creating is new. For all of our longing for the "good old days" I think God has something else in mind. Something we have never seen ... something we cannot imagine ... something that exists only in God's perfection. My prayer is that all who read this post will see this new creation and our Creator face-to-face. May it be so! Randy