"But when the Lord says that God is a Spirit, I think
that Christ spoke thus of the Father, as wishing that
something still more should be understood than merely
that God is a Spirit. For although, in His Gospel, He
is reasoning for the purpose of giving to men an
increase of intelligence, nevertheless He Himself
speaks to men concerning God, in such a way as they
can as yet hear and receive; although, as we have
said, He is now endeavouring to give to His hearers
religious additions to their knowledge of God. For we
find it to be written that God is called Love, and yet
from this the substance of God is not declared to be
Love; and that He is called Light, while in this is
not the substance of God" (De Trinitate 7).
Notice that propositions such as "God is love" or "God is light" are not metaphysical pronouncements (according to this passage), which is to say, Novatian thinks that they do not speak to the divine essence in se. One can find similar reasoning in orthodox writers belonging to the ancient and medieval period.
XAIREIN KAI ERRWSQAI,