And the angel of the LORD appeared unto him in a flame of fire out of the midst of a bush: and he looked, and, behold, the bush burned with fire, and the bush was not consumed.
All Commentaries on Exodus 3:2 Go To Exodus 3
Caesarius of Arles
AD 542
It was not without reason, beloved brethren, nor without the signification of some mystery that there was a flame in the bush: “And the bush was not consumed.” Indeed, the bush was a genus of thorns. What the earth has produced for sinful man cannot be put in any kind of praise, for it was first said to man when he sinned: “Thorns and thistles shall the earth bring forth to you.” The fact that the bush was not burned, that is, was not seized by the flames, is understood to signify no good. In the flame is recognized the Holy Ghost; in the bush and thorns is represented the hard, haughty Jewish people.