But reason asks, was darkness created with the world?  Is it older than light?  Why in spite of its inferiority has it preceded it?  Darkness, we reply, did not exist in essence; it is a condition produced in the air by the withdrawal of light.  What then is that light which disappeared suddenly from the world, so that darkness should cover the face of the deep?  If anything had existed before the formation of this sensible and perishable world, no doubt we conclude it would have been in light.  The orders of angels, the heavenly hosts, all intellectual natures named or unnamed, all the ministering spirits, cf. Heb. i. 14. did not live in darkness, but enjoyed a condition fitted for them in light and spiritual joy. cf. Theod. (Quæst. in Gen. vi.) who is ready to accept the creation of angels before the creation of the world.  Origen, Hom. i. in Gen.  Hom. iv. in Is. taught the existence of angels “before the æons.”  Greg. Naz., Orat. xxxviii.  The lxx. Trans. of Job xxxviii. 7, ᾔνεσάν με πάντες ἄγγελοί μου may have aided in the formation of the general opinion of the Greek Fathers.  The systematization of the hierarchies is due to the pseudo, Dionysius, and was transmitted to the west through John Erigena.  cf. Milman, Lat. Christ. ix. 59.