In Exodus 13:21, this signifies a state of illumination tempered by the obscurity of truth, and a state of obscurity tempered by illumination from good. (Arcana Coelestia 8106, 8108)

In Revelation 10:1, this signifies that the Lord's Divine Natural, which in itself is the Divine Humanity which He took in the world, sustains and supports His Eternal Divinity as the body does the soul, and as the natural sense of the Word does its spiritual and celestial senses; for feet signifies the natural, pillars signify support, and fire, the Divine Love. (Apocalypse Revealed 468)

In Exodus 26:32, this signifies what supports heaven and the church, namely the goods of love and of faith from the Lord. (Arcana Coelestia 9674)

(Odkazy: Exodus 8, 8:21, 21)

468. And his feet like pillars of fire. This symbolizes the Lord's Divinity on the natural plane in respect to His Divine love, which sustains all things.

This, too, is apparent, from the explanation in no. 49 above, where it is said of the Son of Man that "His feet were like fine brass, as though fired in a furnace."

The angel's feet looked like pillars of fire because the Lord's Divinity on the natural plane - which fundamentally is the Divine humanity that He took on in the world - supports His Divinity from eternity, as the body does the soul, and likewise as the Word's natural meaning supports its spiritual and celestial meanings, on which subject see The Doctrine of the New Jerusalem Regarding the Sacred Scripture, nos. 27-49. To be shown that feet symbolize something natural, see no. 49, and a pillar something that supports, no. 191.

Fire symbolizes love because spiritual fire is nothing else. Therefore it is customary in worship to pray that heavenly fire, that is to say, heavenly love, may kindle the worshipers' hearts. People know that there is a correspondence between fire and love from the fact that a person grows warm with love, and cold with its loss. Nothing else produces vital warmth but love, in both senses. The origin of these correspondences is owing to the existence of two suns, one in the heavens, which is pure love, and the other in the world, which is nothing but fire. This, too, is the reason for the correspondence between all spiritual and natural things.

[2] Since fire symbolizes Divine love, therefore on Mount Horeb Jehovah appeared to Moses in a bush on fire (Exodus 3:1-3). Moreover He descended upon Mount Sinai in fire (Deuteronomy 4:36). For this reason, too, the seven lamps of the lampstand in the Tabernacle were lit every evening, so as to burn before Jehovah (Leviticus 24:2-4). For the same reason fire burned continually on the altar and was not extinguished (Leviticus 6:13), and the priests took fire from the altar in their censers and burned incense (Leviticus 16:12-13).

Therefore Jehovah went before the children of Israel by night in a pillar of fire (Exodus 13:21-22). Fire from heaven consumed the burnt offerings on the altar, as a sign of His being well pleased (Leviticus 9:24, 1 Kings 18:38). The burnt offerings were called offerings by fire to Jehovah, and offerings by fire for a restful aroma to Jehovah (Exodus 29:18; Leviticus 1:9, 13, 17; 2:2, 9-11; 3:5, 16; 4:35; 5:12; 7:30; 21:6; Numbers 28:2; Deuteronomy 18:1).

Therefore in the book of Revelation the Lord's eyes looked like a flame of fire (Revelation 1:14; 2:18; 19:12, cf. Daniel 10:5-6). And seven lamps of fire burned before the throne (Revelation 4:5).

It is apparent from this what lamps containing oil and lamps without oil symbolize (Matthew 25:1-11). The oil means fire, and thus love.

And so on in many other places.

In an opposite sense fire symbolizes hellish love, and this is plain from so many passages in the Word that it would be impossible to cite them all because of their number. See something on the subject in the book Heaven and Hell, published in London, nos. 566-575.