Arcana Coelestia #670
670. That 'living creature' 1 means things of the understanding, and 'all flesh' those of the will, becomes clear from what has been stated already, and also from what follows. In the Word 'living creature' means all animal life in general, as in Genesis 1:10, 21, 24; 2:19. Here however, because the phrase 'all flesh' is added immediately after, it means things which belong to the understanding, for the reason given already, that the regeneration of the member of this Church had to begin in the things of the understanding. This also is why in the next verse 'birds' are mentioned first, which mean things of the understanding or the rational, and 'beasts', which are those of the will, second. 'Flesh' in particular means bodily-mindedness which is a feature of the will.
Footnotes:
1. literally, living soul
Exodus 24:10
10
And they saw the God of Israel: and there was under his feet as it were a paved work of a sapphire stone, and as it were the body of heaven in his clearness.