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:

'The spirit of God,' as in Genesis 1:2, signifies the divine mercy of the Lord.

'The spirit of God' denotes good from an interior level, so from the divine. The spirit of God is what proceeds from the divine, so from good itself, because the divine is good itself, and what proceeds from it is truth within which is good. This is what 'the spirit of God' signifies in the Word, because the spirit itself does not proceed, but the truth itself within which is good, the spirit being the instrument which produces it.

(References: Arcana Coelestia 19; Divine Love and Wisdom 100)