Nicene and Post-Nicene Fathers, Ser. II, Vol. V:
Dogmatic Treatises.: He vainly thinks that the doubt about the energies is to be solved by the beings, and reversely.

§29. He vainly thinks that the doubt about the energies is to be solved by the beings, and reversely.

Now let us see what comes next. ‘The doubt about the energies is to be solved by the beings.’ What way is there of bringing this man out of his vain fancies down to common sense? If he thinks that it is possible thus to solve doubts about the energies by comprehending the beings themselves, how, if these last are not comprehended, can he change this doubt to any certainty? If the being has been comprehended, what need to make the energy of this importance, as if it was going to lead us to the comprehension of the being. But if this is the very thing that makes an examination of the energy necessary, viz., that we may be thereby guided to the understanding of the being that exerts it, how can this as yet unknown nature solve the doubt about the energy? The proof of anything that is doubted must be made by means of well-known truths; but when there is an equal uncertainty about both the objects of our search, how can Eunomius say that they are comprehended by means of each other, both being in themselves beyond our knowledge? When the Father’s being is under discussion, he tells us that the question may be settled by means of the energy which follows Him and of the work which this energy accomplishes; but when the inquiry is about the being of the Only-begotten, whether Eunomius calls Him an energy or a product of the energy (for he does both), then he tells us that the question may be easily solved by looking at the being of His producer!