New Defender's Study Bible Notes
21:2 I John. This is the first time that John has identified himself by name since the very beginning (Revelation 1:1, 4, 9) of his message. The scene before his eyes was so magnificent that he must emphasize that he himself was really there observing it.
21:2 out of heaven. The new Jerusalem is not synonymous with heaven, as many think, for it will come “down from God out of heaven,” and then be established on the new earth, there to remain forever.
21:2 bride. The gloriously white city reminds John of a bride coming to her husband, and is even called “the bride, the Lamb’s wife” (Revelation 21:9; see also Revelation 19:7-9; 22:17; Ephesians 5:25-27).