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)

(Riferimenti: Exodus 8, 8:21, 21)