362. I heard the second animal saying. That this signifies out of the inmost heaven from the Lord, is clear from what was said above (n. 353); for by the animals are meant the cherubim, and the cherubim signify, in the highest sense, the Lord as to Providence, and as to defence, that He may not be approached except by means of the good of love; and in a respective sense, the inmost heaven (see above, n. 152, 277, 313, 322). The reason why the cherubim also signify the inmost heaven, is, because this heaven is in the good of love to the Lord, and the Lord cannot be approached except through the heavens, and into the inmost or third heaven there is not anything admitted which does not savour of the good of that heaven. The reason there were four animals or cherubim, is, because four signifies conjunction into one, and such is the conjunction with those who are there; for the Lord thus conjoins them by love to Him from Him. Hence it is that four were seen. From these things it is also evident, that the same is here meant by the second animal as by the first, and also by the third and fourth in the verses following. (That four signifies conjunction, may be seen in n. 1686, 8877, 9601, 9674.)

353. And I heard one of the four animals saying as with a voice of thunder. That this signifies, out of the inmost heaven from the Lord, is clear from the signification of the four animals or cherubim, as denoting, in the highest sense, the Lord's Divine Providence and protection lest any one should approach except through the good of love (concerning which see above, n. 152, 277); and [as denoting], in a respective sense, the inmost and third heaven (concerning which also see above, n. 313, 322); and from the signification of a voice of thunder, as denoting manifestation thence. That by lightnings, thunderings, and voices in the Word, are signified enlightening, understanding, and perception, may be seen above, n. 273, hence also manifestation. That thunders signify manifestation out of the inmost heaven is from correspondence; for the voices which flow down out of that heaven even into the hearing of man, are not otherwise heard, for they fill the whole brain (cerebrum), and thence propagate themselves towards the hearing, and are there perceived by such a sound. It is different with the voices that flow down out of the middle heaven. These, since they flow in with enlightenment, are therefore heard sonorously like the expressions of speech.

[2] The reason is, because the things that flow down out of the inmost or third heaven enter man's Voluntary, and the Voluntary is made known by sounds; but the things that flow down out of the middle or second heaven, enter into man's Intellectual, and the Intellectual is made known by the articulations of sound; for sounds are formed in the understanding; and sounds formed, which are called its articulations, manifest themselves by ideas in the thought, and by expressions in the hearing. Hence it is that those things that flow down out of the inmost or third heaven correspond to thunder, and those out of the middle or second heaven to lightning; and hence also it is that in the Word, by lightnings and thunderings are signified enlightenment, understanding, and perception. These have a likeness with sounds in the world, which increase when they descend from heights, as from high mountains into valleys, and also as when from the clouds towards the earth, whence thunderings [are heard]; thus also the voices out of the third or highest heaven, when they are rolled towards the lower parts, and at length into the lowest, in which is human hearing, are heard as thunderings, but only by those who have their interiors opened, as John's then were.