Revelation 21:1

A new heaven and a new earth

(ουρανον καινον κα γην καινην). This new vision (ειδον) is the picture of the bliss of the saints.The first heaven and the first earth

(ο πρωτος ουρανος κα η πρωτη γη)are passed away

(απηλθαν, went away, second aorist active indicative of απερχομα). "Fled away" (εφυγεν) in Revelation 20:11.And the sea is no more

(κα η θαλασσα ουκ εστιν ετ). The sea had given up its dead (Revelation 20:13). There were great risks on the sea (Revelation 18:17). The old physical world is gone in this vision. It is not a picture of renovation of this earth, but of the disappearance of this earth and sky (not heaven where God dwells). It is a glorious picture here in Revelation 21:1-8 in sharp contrast to the lake of fire in Revelation 20:11-15. The symbolism in neither case is to be pressed too literally, but a stern and a glorious reality exists behind it all.