Concerning the energies in our Lord Jesus Christ
But further, if personality is introduced along with energy, those who divine that neither one nor two energies of Christ are to be spoken of, do not maintain that either one or two persons of Christ are to be spoken of.
Take the case of the flaming sword; just as in it the natures of the fire and the steel are preserved distinct, so also are their two energies and their effects. For the energy of the steel is its cutting power, and that of the fire is its burning power, and the cut is the effect of the energy of the steel, and the burn is the effect of the energy of the fire: and these are kept quite distinct in the burnt cut, and in the cut burn, although neither does the burning take place apart from the cut after the union of the two, nor the cut apart from the burning: and we do not maintain on account of the twofold natural energy that there are two flaming swords, nor do we confuse the essential difference of the energies on account of the unity of the flaming sword. In like manner also, in the case of Christ, His divinity possesses an energy that is divine and omnipotent while His humanity has an energy such as is our own. And the effect of His human energy was His taking the child by the hand and drawing her to Himself, while that of His divine energy was the restoring of her to life. For the one is quite distinct from the other, although they are inseparable from one another in theandric energy. But if, because Christ has one subsistence, He must also have one energy, then, because He has one subsistence, He must also have one essence.
And again: if we should hold that Christ has but one energy, this must be either divine or human, or neither. But if we hold that it is divine we must maintain that He is God alone, stripped of our humanity. And if we hold that it is human, we shall be guilty of the impiety of saying that He is mere man. And if we hold that it is neither divine nor human, we must also hold that He is neither God nor man, of like essence neither to the Father nor to us. For it is as a result of the union that the identity in hypostasis arises, but yet the difference between the natures is not done away with. But since the difference between the natures is preserved, manifestly also the energies of the natures will be preserved. For no nature exists that is lacking in energy.
If Christ our Master has one energy, it must be either created or uncreated; for between these there is no energy, just as there is no nature. If, then, it is created, it will point to created nature alone, but if it is uncreated, it will betoken uncreated essence alone. For that which is natural must completely correspond with its nature: for there cannot exist a nature that is defective. But the energy that harmonises with nature does not belong to that which is external: and this is manifest because, apart from the energy that harmonises with nature, no nature can either exist or be known. For through that in which each thing manifests its energy, the absence of change confirms its own proper nature.
If Christ has one energy, it must be one and the same energy that performs both divine and human actions. But there is no existing thing which abiding in its natural state can act in opposite ways: for fire does not freeze and boil, nor does water dry up and make wet. How then could He Who is by nature God, and Who became by nature man, have both performed miracles, and endured passions with one and the same energy?
If, then, Christ assumed the human mind, that is to say, the intelligent and reasonable soul, undoubtedly He has thought, and will think for ever. But thought is the energy of the mind: and so Christ, as man, is endowed with energy, and will be so for ever.
Indeed, the most wise and great and holy John Chrysostom says in his interpretation of the Acts, in the second discourse, “One would not err if he should call even His passion action: for in that He suffered all things, He accomplished that great and marvellous work, the overthrow of death, and all His other works.”
If all energy is defined as essential movement of some nature, as those who are versed in these matters say, where does one perceive any nature that has no movement, and is completely devoid of energy, or where does one find energy that is not movement of natural power? But, as the blessed Cyril says, no one in his senses could admit that there was but one natural energy of God and His creation. It is not His human nature that raises up Lazarus from the dead, nor is it His divine power that sheds tears: for the shedding of tears is peculiar to human nature while the life is peculiar to the enhypostatic life. But yet they are common the one to the other, because of the identity in subsistence. For Christ is one, and one also is His person or subsistence, but yet He has two natures, one belonging to His humanity, and another belonging to His divinity. And the glory, indeed, which proceeded naturally from His divinity became common to both through the identity in subsistence, and again on account of His flesh that which was lowly became common to both. For He Who is the one or the other, that is God or man, is one and the same, and both what is divine and what is human belong to Himself. For while His divinity performed the miracles, they were not done apart from the flesh, and while His flesh performed its lowly offices, they were not done apart from the divinity. For His divinity was joined to the suffering flesh, yet remaining without passion, and endured the saving passions, and the holy mind was joined to the energising divinity of the Word, perceiving and knowing what was being accomplished.
And thus His divinity communicates its own glories to the body while it remains itself without part in the sufferings of the flesh. For His flesh did not suffer through His divinity in the same way that His divinity energised through the flesh. For the flesh acted as the instrument of His divinity. Although, therefore, from the first conception there was no division at all between the two forms, but the actions of either form through all the time became those of one person, nevertheless we do not in any way confuse those things that took place without separation, but recognise from the quality of its works what sort of form anything has.
Christ, then, energises according to both His natures and either nature energises in Him in communion with the other, the Word performing through the authority and power of its divinity all the actions proper to the Word, i.e. all acts of supremacy and sovereignty, and the body performing all the actions proper to the body, in obedience to the will of the Word that is united to it, and of whom it has become a distinct part. For He was not moved of Himself to the natural passions, nor again did He in that way recoil from the things of pain, and pray for release from them, or suffer what befell from without, but He was moved in conformity with His nature, the Word willing and allowing Him œconomically to suffer that, and to do the things proper to Him, that the truth might be confirmed by the works of nature.
Moreover, just as He received in His birth of a virgin superessential essence, so also He revealed His human energy in a superhuman way, walking with earthly feet on unstable water, not by turning the water into earth, but by causing it in the superabundant power of His divinity not to flow away nor yield beneath the weight of material feet. For not in a merely human way did He do human things: for He was not only man, but also God, and so even His sufferings brought life and salvation: nor yet did He energise as God, strictly after the manner of God, for He was not only God, but also man, and so it was by touch and word and such like that He worked miracles.
Source: Exposition of the Faith (New Advent)