And he that sat was to look upon like a jasper and a carnelian stone: and there was a rainbow round about the throne, in appearance like unto an emerald.
All Commentaries on Revelation 4:3 Go To Revelation 4
Bede
AD 735
jasper: The colour of the jasper signifies water, of the sard fire, and we know that judgement is represented by these two. For "as it was," He says, "in the days of Noah, so shall also the coming of the Son of Man be."