Apocalypse Revealed # 228
228. Immediately I was in the spirit. This symbolizes John's conveyance into a spiritual state, in which the things that occur in heaven clearly appear.
It may be seen in no. 36 above that to be in the spirit is to be conveyed into a spiritual state by a Divine influx. It may be seen there also what a spiritual state is, the nature of it, and the fact that a person in that state sees the phenomena in the spiritual world as clearly as he sees the phenomena in this world when in the natural state of the body.
Daniel 7:9-10
9
I beheld till the thrones were cast down, and the Ancient of days did sit, whose garment was white as snow, and the hair of his head like the pure wool: his throne was like the fiery flame, and his wheels as burning fire.
10
A fiery stream issued and came forth from before him: thousand thousands ministered unto him, and ten thousand times ten thousand stood before him: the judgment was set, and the books were opened.