Revelation 4:6

And before the throne there was a sea of glass like unto crystal: and in the midst of the throne, and round about the throne, were four beasts full of eyes before and behind.

Ver. 6. A sea of glass] The word, say some; the world, others. The word is to us a crystal glass, giving us a clear sight of God and of ourselves, 2 Corinthians 3:18; James 1:23. The world is to God a sea of glass, corpus diaphanum, a clear transparent body, he sees through it.

Four beasts] ζωα, or living wights; a not angels, but ministers, those earthly angels, who are set forth, 1. Full of eyes for their perspicacity and vigilancy. 2. Furnished with six wings apiece for their pernicity and promptitude to scour about for the people's benefit. 3. Qualified with all necessary endowments, for the discharge of their duties, being bold as lions, painful as oxen, prudent as men, delighted in high flying, as eagles.

a A living being in general; a creature. Obs. OED