St. Maximus the Confessor ca. 580-662
How did the Word Incarnate truly become a human being, if he lacked that which best characterizes a nature as rational? For what is deprived of the movement of longing that follows desire has no share in any power of life. And that which does not possess any power of life out of its nature is clearly not a soul of any kind, without which the flesh is not what it is. Therefore the economy would be a mere fantasy, if he merely had the shape of flesh. But if, as Severus said, he did not have, as man, a natural will, the Word Incarnate would not fulfill the hypostatic union with flesh, endowed by nature with a rational soul and intellect. For if he was truly, as man, lacking a natural will, he would not truly have become perfect man. And if he did not truly become perfect man, he did not become man at all. For what kind of existence does an imperfect nature have, since its principle of existence no longer exists? The purport therefore of Severus, and his followers, is by a certain natural diminishment to expel the assumed nature in the ineffable union, and to cover themselves with the defilement of Mani’s fantasy, Apollinaris’ confusion, and Eutyches’ fusion. I remember when I was staying in the island of Crete, that I heard from certain false bishops of the Severan party, who disputed with me, that ‘we do not say, in accordance with The Tome of Leo, that there are two energies in Christ, because it would follow that there are two wills, and that would necessarily introduce a duality of persons, nor again do we say one energy, which might be regarded as simple, but we say, in accordance with Severus, that one will, and every divine and human energy proceeds from one and the same God the Word Incarnate.’ Against them one might angrily apply that part of the prophecy: “O, O, flee from the north; in Zion you are saved, you who inhabit the daughter of Babylon.” (Zec. 2:6-7) From the north: that is truly the understanding of Severus, a place become gloomy, and deprived of divine the continuance of the divine light. Daughter of Babylon: the confided teaching of false dogmas, wickedly brought forth from the most wicked habit picked up from him, which those inhabit, who have turned away from the light of knowledge, and not with those to be saved through conversion to Zion, I mean the Church.
For the doctrine of Severus, when examined is opposed both to theology and to the economy. (Opuscule 3)