854. (Verse 2) And I heard a voice out of heaven, as the voice of many waters. That this signifies the glorification of the Lord from the Divine truths, which are from Himself, is clear from the signification of a voice out of heaven, as denoting the glorification of the Lord. For a voice out of heaven involves the things that are spoken therefrom, and which now follow, and are especially contained in the new song, by which is signified acknowledgment and confession of the Lord; and from the signification of many waters, as denoting Divine truths, which are from the Lord.

That by waters, in the Word, are signified Divine truths, may be seen above (n. 71, 483, 518). And because waters have such a signification, therefore speech is sometimes heard from heaven like the sound of flowing waters; just as the voice of the Son of man walking in the midst of the lamp-stands was heard;

Whose "voice was as the sound of many waters" (Apoc. 1:15).

And in the following:

"I heard the voice of a great trumpet, and as the voice of many waters, and as it were the voice of mighty thunderings" (Apoc. 19:6).

Similarly

The sound of the wings of the cherubs was heard as the sound of great waters (Ezekiel 1:24).