'The first resurrection,' mentioned in Revelation 20:5, 6, does not mean a first resurrection, but the essence and primary part of resurrection, which is salvation and eternal life. There is only one resurrection to life. A second does not happen, and is not mentioned anywhere in the Bible.

(References: Apocalypse Explained 6; Apocalypse Revealed 851; Revelation 20:5-6)

1379. These considerations also show that when spirits walk or are removed and advance from one place to another - occurrences witnessed very frequently - nothing else than changes of state are taking place. That is, such changes appear in the world of spirits as changes of place, but in heaven as changes of state. The same applies to many other things that are representative and present themselves visually there. In the Lord's Divine mercy these will be dealt with later on.