If this be true, the question as to his attitude towards Plato, which is one of the first that suggests itself, is settled. Against polytheism he does indeed seek to defend Christianity by connecting it apologetically with Plato's system. This we cannot be surprised at, considering that the definitions of the doctrines of the Catholic Church were formed in the very place where the last considerable effort of Platonism was made; but he by no means makes the New Life in any way dependent on this system of philosophy. "We cannot speculate," he says (De Anim. et Resurrect.),..."we must leave the Platonic car." But still when he is convinced that Plato will confirm doctrine he will, even in polemic treatises, adopt his view; for instance, he seeks to grasp the truth of the Trinity from the Platonic account of our internal consciousness, i.e. psuche, logos, nous; because such a proof from consciousness is, to Gregory, the surest and most reliable.
The "rational considerations," then, by which Gregory would have established Christian doctrine are not necessarily drawn from the philosophy of the time: nor, further, does he seek to rationalize entirely all religious truth. In fact he resigns the hope of comprehending the Incarnation and all the great articles. This is the very thing that distinguishes the Catholic from the Eunomian. "Receiving the fact we leave untampered with the manner of the creation of the Universe, as altogether secret and inexplicable  ." With a turn resembling the view of Tertullian, he comes back to the conclusion that for us after all Religious Truth consists in mystery. "The Church possesses the means of demonstrating these things: or rather, she has faith, which is surer than demonstration  ." He developes the truth of the Resurrection as much by the fulfilment of God's promises as by metaphysics: and it has been considered as one of the proofs that the treatise What is being in the image of God'? is not his that this subordination of philosophical proof to the witness of the Holy Spirit is not preserved in it.
Nevertheless there was a large field, larger even than in the next century, in which rationalizing was not only allowable, but was even required of him. In this there are three questions which Gregory has treated with particular fulness and originality. They are: -- 1. Evil; 2. The relation between the ideal and the actual Man; 3. Spirit.
I. He takes, to begin with, Origen's view of evil. Virtue and Vice are not opposed to each other as two Existencies: but as Being is opposed to not-Being. Vice exists only as an absence. But how did this arise?
In answering this question he seems sometimes to come very near Manicheism, and his writings must be read very carefully, in order to avoid fixing upon him the groundless charge that he leaves evil in too near connexion with Matter. But the passages  which give rise to this charge consist of comparisons found in his homilies and meditations; just as a modern theologian might in such works make the Devil the same as Sin and Death. The only imperfection in his view is that he is unable  to regard evil as not only suffered but even permitted by God. But this imperfection is inseparable from his time: for Manicheism was too near and its opposition too little overcome for such a view to be possible for him; he could not see that it is the only one able thoroughly to resist Dualism.
Evil with Gregory is to be found in the spontaneous proclivity of the soul towards Matter: but not in Matter itself. Matter, therefore, in his eschatology is not to be burnt up and annihilated: only soul and body have to be refined, as gold (this is a striking comparison) is refined. He is very clear upon the relations between the three factors, body, matter, and evil. He represents the mind as the mirror of the Archetypal Beauty: then below the mind comes body (phusis which is connected with mind and pervaded by it, and when thus transfigured and beautified by it becomes itself the mirror of this mirror: and then this body in its turn influences and combines Matter. The Beauty of the Supreme Being thus penetrates all things: and as long as the lower holds on to the higher all is well. But if a rupture occurs anywhere, then Matter, receiving no longer influence from above, reveals its own deformity, and imparts something of it to body and, through that, to mind: for matter is in itself a shapeless unorganized thing  .' Thus the mind loses the image of God. But evil began when the rupture was made: and what caused that? When and how did the mind become separated from God?
Gregory answers this question by laying it down as a principle, that everything created is subject to change. The Uncreate Being is changeless, but Creation, since its very beginning was owing to a change, i.e. a calling of the non-existent into existence, is liable to alter. Gregory deals here with angelic equally as with human nature, and with all the powers in both, especially with the will, whose virtual freedom he assumes throughout. That, too, was created; therefore that, too, could change.
It was possible, therefore, that, first, one of the created spirits, and, as it actually happened, he who was entrusted with the supervision of the earth, should choose to turn his eyes away from the Good; he thus looked at a lower good; and so began to be envious and to have pathe. All evil followed in a chain from this beginning; according to the principle that the beginning of anything is the cause of all that follows in its train.
So the Devil fell: and the proclivity to evil was introduced into the spiritual world. Man, however, still looked to God and was filled with blessings (this is the ideal man' of Gregory). But as when the flame has got hold of a wick one cannot dim its light by means of the flame itself, but only by mixing water with the oil in the wick, so the Enemy effected the weakening of God's blessings in man by cunningly mixing wickedness in his will, as he had mixed it in his own. From first to last, then, evil lies in the proairesis and in nothing else.
God knew what would happen and suffered it, that He might not destroy our freedom, the inalienable heritage of reason and therefore a portion of His image in us.  He gave scope to evil for a nobler end.' Gregory calls it a piece of "little mindedness" to argue from evil either the weakness or the wickedness of God.
II. His remarks on the relation between the ideal and the actual Man are very interesting. It is usual with the other Fathers, in speaking of man's original perfection, to take the moment of the first man's residence in Paradise, and to regard the whole of human nature as there represented by the first two human beings. Gregory is far removed from this way of looking at the matter. With him human perfection is the idea' of humanity: he sees already in the bodily-created Adam the fallen man. The present man is not to be distinguished from that bodily Adam; both fall below the ideal type. Gregory seems to put the Fall beyond and before the beginning of history. Under the form of narrative Moses places before us mere doctrine  .' The locus classicus about the idea and the reality of human nature is On the Making of Man, I. p.88f. He sketches both in a masterly way. He speaks of the division of the human race into male and female as a device' (epitechnesis), implying that it was not the first organization' (kataskeue). He hints that the irrational element was actually provided by the Creator, Who foresaw the Fall and the Redemption, for man to sin in; as if man immediately upon the creation of the perfect humanity became a mixed nature (spirit and flesh), and his fall was not a mere accident, but a necessary consequence of this mixed nature. Adam must have fallen: there was no perfect humanity in Paradise. In man's mixed nature of spirit and flesh nutrition is the basis of his sensation, and sensation is the basis of his thought; and so it was inevitable that sin through this lower yet vital side of man should enter in. So ingrained is the spirit with the flesh in the whole history of actual humanity that all the varieties of all the souls that ever have lived or ever shall, arise from this very mixture; i.e. from the varying degrees of either factor in each. But as Gregory's view here touches, though in striking contrast, on Origen's, more will be said about it in the next chapter.
It follows from this that Gregory, as Clement and Basil before him, did not look upon Original Sin as the accidental or extraordinary thing which it was afterwards regarded. From a man who is a sinner and subject to passion of course is engendered a man who is a sinner and subject to passion: sin being in a manner born with him, and growing with his growth, and not dying with it.' And yet he says elsewhere, "An infant who is just born is not culpable, nor does it merit punishment; just as he who has been baptized has no account to give of his past sins, since they are forgiven," and he calls infants aponeroi, not having in the least admitted the disease into their soul.' But these two views can of course be reconciled; the infant at the moment of its physical birth starts with sins forgotten, just as at the moment of its spiritual birth it starts with sins forgiven. No actual sin has been committed. But then its nature has lost the apatheia; the inevitable weakness of its ancestry is in it.
III. Spirit.' Speaking of the soul, Gregory asks, How can that which is incomposite be dissolved?' i.e. the soul is spirit, and spirit is incomposite and therefore indestructible.
But care must be taken not to infer too much from this his favourite expression spirit' in connexion with the soul. God is spirit' too; and we are inclined to forget that this is no more than a negative definition, and to imagine the human spirit of equal prerogative with Deity. Gregory gives no encouragement to this; he distinctly teaches that, though the soul is incomposite, it is not in the least independent of time and space, as the Deity is.
In fact he almost entirely drops the old Platonic division of the Universe into Intelligible (spiritual) and Sensible, which helps to keep up this confusion between human and divine spirit,' and adopts the Christian division of Creator and Created. This difference between Creator and Created is further figured by him as that between
1. The Infinite and The Finite.
2. The Changeless and The Changeable.
3. The Contradiction-less and The Contradictory.
The result of this is that the Spirit-world itself has been divided into Uncreate and Created.
With regard, then, to this created Spirit-world we find that Gregory, as Basil, teaches that it existed, i.e. it had been created, before the work of the Six Days began. God made all that is, at once' (athroos). This is only his translation of the verse, In the beginning God created the heaven and the earth;' the material for heaven' and earth,' i.e. spirits and chaos, was made in a moment, but God had not yet spoken the successive Words of creation. The souls of men, then, existed from the very beginning of creation, and in a determinate number; for this is a necessary consequence of the simultaneous creation.' This was the case with the Angels too, the other portion of the created Spirit-world. Gregory has treated the subject of the Angels very fully. He considers that they are perfect: but their perfection too is contingent: it depends on the grace of God and their own wills; the angels are free, and therefore changeable. Their will necessarily moves towards something: at their first creation the Beautiful alone solicited them. Man a little lower than the Angels' was perfect too; deathless, passionless, contemplative. The true and perfect soul is single in its nature, intellectual, immaterial  .' He was as the Angels' and if he fell, Lucifer fell too. Gregory will not say, as Origen did, that human souls had a body when first created: rather, as we have seen, he implies the contrary; and he came to be considered the champion that fought the doctrine of the pre-existence of embodied souls. He seems to have been influenced by Methodius' objections to Origen's view. But his magnificent idea of the first man gives way at once to something more Scriptural and at the same time more scientific; and his ideal becomes a downright forecast of Realism.
Taking, however, the human soul as it is, he still continues, we often find, to compare it with God. In his great treatise On the Soul and the Resurrection, he rests a great deal on the parallel between the relation of man to his body, and that of God to the world. -- The soul is as a cord drawn out of mud; God draws to Himself what is His own.' -- He calls the human spirit an influx of the divine in-breathing' (Adv. Apollin. c.12). Anger and desire do not belong to the essence of the soul, he says: they are only among its varying states. The soul, then, as separable from matter, is like God. But this likeness does not extend to the point of identity. Incomprehensible, immortal, it is not uncreated. The distinction between the Creator and the Created cannot be obliterated. The attributes of the Creator set down above, i.e. that He is infinite, changeless, contradictionless, and so always good, &c., can be applied only catachrestically to some men, in that they resemble their Maker as a copy resembles its original: but still, in this connexion, Gregory does speak of those who do not need any cleansing at all  ,' and the context forces us to apply these words to men. There is no irony, to him or to any Father of the fourth century, in the words, They that are whole need not a physician.' Although in the treatise On Virginity, where he is describing the development of his own moral and religious life, he is very far from applying them to himself, he nevertheless seems to recognize the fact that since Christianity began there are those to whom they might apply.
There is also need of a certain amount of rational considerations' in advancing a Defence and a Theory of Christianity. He makes this according to the special requirements of the time in his Oratio Catechetica. His reasonings do not seem to us always convincing; but the presence of a living Hellenism and Judaism in the world required them. These two phenomena also explain what appears to us a great weakness in this work: namely, that he treats Hellenism as if it were all speculation; Judaism as if it were all facts. These two religions were too near and too practically opposed to each other for him to see, as we can now, by the aid of a sort of science of religions, that every religion has its idea, and every religion has its facts. He and all the first Apologists, with the spectacle of these two apparently opposite systems before them, thought that, in arriving at the True Religion as well, all could be done by considering facts; or all could be done by speculation. Gregory chose the latter method. A Dogmatic in the modern sense, in which both the idea and the facts of Christianity flow into one, could not have been expected of him. The Oratio Catechetica is a mere philosophy of Christianity in detail written in the philosophic language of the time. Not only does he refrain from using the historic proofs, i.e. of prophecy and type (except very sparingly and only to meet an adversary), but his defence is insufficient from another point of view also; he hardly uses the moral proofs either; he wanders persistently in metaphysics.
If he does not lean enough on these two classes of proofs, at all events that he does not lean entirely on either, may be considered as a guarantee of his excellence as a theologian pure and simple. But he is on the other hand very far from attempting a philosophic construction of Christianity, as we have seen. Though akin to modern theologians in many things, he is unlike those of them who would construct an a priori Christianity, in which the relationship of one part to another is so close that all stands or falls together. Philosophic deduction is with him only a kind of instruction' used in his apologetic works. On occasion he shows a clear perception of the historic principle. "The supernatural character of the Gospel miracles bears witness to their divine origin  ." He points, as Origen did, to the continued possession of miraculous powers in the Church. Again, as regards moral proof, there had been so much attempted that way by the Neo-Platonists that such proof could not have exactly the same degree of weight attributed to it that it has now, at least by an adherent of the newer Hellenism. Philostratus, Porphyry, Iamblichus had all tried to attract attention to the holy lives of heathen sages. Yet to these, rough sketches as they were, the Christian did oppose the Lives of the Saints: notably Gregory himself in the Life of Gregory Thaumaturgus: as Origen before him (c. Celsum, passim) had shewn in detail the difference in kind of Christian holiness.
His treatment of the Sacraments in the Oratio Catechetica is noteworthy. On Baptism he is very complete: it will be sufficient to notice here the peculiar proof he offers that the Holy Spirit is actually given in Baptism. It is the same proof, to start with, as that which establishes that God came in the flesh when Christ came. Miracles prove this; (he is not wanting here in the sense of the importance of History). If, then, we are persuaded that God is here, we must allow also that truth is here: for truth is the mark of Deity. When, therefore, God has said that He will come in a particular way, if called in a particular way, this must be true. He is so called in Baptism: therefore He comes. (The vital importance of the doctrine of the Trinity, upon which Gregory laboured for so many years, thus all comes from Baptism.) Gregory would not confine the entire force of Baptism to the one ritual act. A resurrection to a new immortal life is begun in Baptism, but owing to the weakness of nature this complete effect is separated into stages or parts. With regard to the necessity of Baptism for salvation, he says he does not know if the Angels receive the souls of the unbaptized; but he rather intimates that they wander in the air seeking rest, and entreat in vain like the Rich Man. To him who wilfully defers it he says, You are out of paradise, O Catechumen!'
In treating the Sacrament of the Eucharist, Gregory was the first Father who developed the view of transformation, for which transubstantiation was afterwards substituted to suit the mediæval philosophy; that is, he put this view already latent into actual words. There is a locus classicusin the Oratio Catechetica, c.37.
"Therefore from the same cause as that by which the bread that was transformed in that Body was changed to a divine potency, a similar result takes place now. For as in that case, too, the grace of the Word used to make holy the Body, the substance of which came of the bread and was in a manner itself bread, so also in this case the bread, as says the Apostle, is sanctified by the word of God and prayer:' not that it advances by the process of eating to the stage of passing into the body of the Word, but it at once is changed into the Body, by the Word, as the Word Himself said, This is My Body;'" and just above he had said: "Rightly do we believe that now also the bread which is consecrated by the word of God is changed into the body of God the Word." This way of explaining the mystery of the Sacrament, i.e. from the way bread was changed into the Word when Christ was upon earth, is compared by Neander with another way Gregory had of explaining it, i.e. the heightened efficacy of the bread is as the heightened efficacy of the baptismal water, the anointing oil  , &c., a totally different idea. But this, which may be called the metabatic view, is the one evidently most present to his mind. In a fragment of his found in a Parisian ms.  , quoted with the Liturgies of James, Basil, Chrysostom, we also find it; "The consecrated bread is changed into the body of the Word; and it is needful for humanity to partake of that."
Again, the necessity of the Incarnation, drawn from the words "it was necessary that Christ should suffer," receives a rational treatment from him. There must ever be, from a meditation on this, two results, according as the physical or the ethical element in Christianity prevails, i.e.1. Propitiation; 2. Redemption. The first theory is dear to minds fed upon the doctrines of the Reformation, but it receives no countenance from Gregory. Only in the book in which Moses' Life is treated allegorically does he even mention it. The sacrifice of Christ instead of the bloody sacrifices of the Old Testament is not his doctrine, He develops his theory of the Redemption or Ransom (i.e. from the Devil), in the Oratio Catechetica. Strict justice to the Evil One required it. But in his hands this view never degenerates, as with some, into a mere battle, e.g. in Gethsemane, between the Rescuer and Enslaver.
So much has been said about Gregory's inconsistencies, and his apparent inconsistencies are indeed so many, that some attempt must be made to explain this feature, to some so repulsive, in his works. One instance at all events can show how it is possible to reconcile even the most glaring. He is not a one-sided theologian: he is not one of those who pass always the same judgment upon the same subject, no matter with whom he has to deal. There could not be a harsher contradiction than that between his statement about human generation in the Oratio Catechetica, and that made in the treatises On Virginity and On the Making of Man. In the O.C. everything hateful and undignified is removed from the idea of our birth; the idea of pathos is not applied; "only evil brings disgrace." But in the other two Treatises he represents generation as a consequence of the Fall. This contradiction arises simply from the different standpoint in each. In the one case he is apologetic; and so he adopts a universally recognised moral axiom. In the other he is the Christian theologian; the natural process, therefore, takes its colouring from the Christian doctrine of the Fall. This is the standpoint of most of his works, which are polemical, not apologetic. But in the treatise On the Soul and the Resurrection he introduces even a third view about generation, which might be called that of the Christian theosophist; i.e. generation is the means in the Divine plan for carrying Humanity to its completion. Very similar is the view in the treatise On Infants' Early Deaths; "the design of all births is that the Power which is above the universe may in all parts of the creation be glorified by means of intellectual natures conspiring to the same end, by virtue of the same faculty operating in all; I mean, that of looking upon God." Here he is speaking to the purely philosophic instinct. It may be remarked that on this and all the operations of Divine foreknowledge in vast world-wide relations he has constantly striking passages, and deserves for this especially to be studied.
The style of Gregory is much more elegant than that of Basil: sometimes it may be called eloquent. His occasional digressions did not strike ancient critics as a fault. To them he is "sweet," "bright," "dropping pleasure into the ears." But his love for splendour, combined with the lateness of his Greek, make him one of the more difficult Church writers to interpret accurately.
His similes and illustrations are very numerous, and well chosen. A few exceptions must, perhaps, be made. He compares the mere professing Christian to the ape, dressed like a man and dancing to the flute, who used to amuse the people in the theatre at Alexandria, but once revealed during the performance its bestial nature, at the sight of food. This is hardly worthy of a great writer, as Gregory was  . Especially happy are his comparisons in the treatise On the Soul and Resurrection, by which metaphysical truths are expressed; and elsewhere those by which he seeks to reach the due proportions of the truth of the Incarnation. The chapters in his work against Eunomius where he attempts to depict the Infinite, are striking. But what commends him most to modern taste is his power of description when dealing with facts, situations, persons: he touches these always with a colour which is felt to be no exaggeration, but the truth.
 Cp. Or. Cat. c. xi.  In verba faciamus hominem,' I.[p. 140.  De Perf. Christiani Forma, III. p. 294, he calls the Prince of darkness' the author of sin and death: In Christi Resurrect. III. p. 386, he calls Satan the heart of the earth:' and p. 387 identifies him with sin. And so the real wisdom visits that arrogant heart of the earth, so that the thought great in wickedness should vanish, and the darkness should be lightened, &c.'  As expressed by S. Thomas Aquinas Summ. I. Qu. xix. Art. 9, Deo nec nolente, nec volente, sed permittente....Deus neque vult fieri, neque vult non fieri, sed vult permittere mala fieri.  De Virginit. c. xi.  On Infants' early Deaths, III.[p. 336.  Or. Cat. c. viii. D.  On the Making of Man, c. xiv.  Or. Cat. c. xxvi.  Or. Cat. c. iii.  In Sermon On the Baptism of Christ.  A. 1560 fol.; also Antwerp, p. 1562 (Latinè).  His comparison of the hidden meaning of the proverb or parable (III. c. Eunom. p. 236) to the turned up' side of the peacock's feather is beautiful in itself for language (e.g. the varied painting of nature,' the half-circle shining in the midst with its dye of purple,' the golden mist round the circle'): but it rather fails as a simile, when applied to the other or the literal side, which cannot in the case of parables be said to lack beauty and tint'.
 In verba faciamus hominem,' I.[p. 140.
 De Perf. Christiani Forma, III. p. 294, he calls the Prince of darkness' the author of sin and death: In Christi Resurrect. III. p. 386, he calls Satan the heart of the earth:' and p. 387 identifies him with sin. And so the real wisdom visits that arrogant heart of the earth, so that the thought great in wickedness should vanish, and the darkness should be lightened, &c.'
 As expressed by S. Thomas Aquinas Summ. I. Qu. xix. Art. 9, Deo nec nolente, nec volente, sed permittente....Deus neque vult fieri, neque vult non fieri, sed vult permittere mala fieri.
 De Virginit. c. xi.
 On Infants' early Deaths, III.[p. 336.
 Or. Cat. c. viii. D.
 On the Making of Man, c. xiv.
 Or. Cat. c. xxvi.
 Or. Cat. c. iii.
 In Sermon On the Baptism of Christ.
 A. 1560 fol.; also Antwerp, p. 1562 (Latinè).
 His comparison of the hidden meaning of the proverb or parable (III. c. Eunom. p. 236) to the turned up' side of the peacock's feather is beautiful in itself for language (e.g. the varied painting of nature,' the half-circle shining in the midst with its dye of purple,' the golden mist round the circle'): but it rather fails as a simile, when applied to the other or the literal side, which cannot in the case of parables be said to lack beauty and tint'.