This work was intended to supplement and complete the Hexaëmeron of S. Basil, and presupposes an acquaintance with that treatise. The narrative of the creation of the world is not discussed in detail: it is referred to, but chiefly in order to insist on the idea that the world was prepared to be the sphere of man's sovereignty. On the other hand, Gregory shows that man was made "with circumspection," fitted by nature for rule over the other creatures, made in the likeness of God in respect of various moral attributes, and in the possession of reason, while differing from the Divine nature in that the human mind receives its information by means of the senses and is dependent on them for its perception of external things. The body is fitted to be the instrument of the mind, adapted to the use of a reasonable being: and it is by the possession of the "rational soul," as well as of the "natural" or "vegetative" and the "sensible" soul, that man differs from the lower animals. At the same time, his mind works by means of the senses: it is incomprehensible in its nature (resembling in this the Divine nature of which it is the image), and its relation to the body is discussed at some length (chs. 12-15). The connection between mind and body is ineffable: it is not to be accounted for by supposing that the mind resides in any particular part of the body: the mind acts upon and is acted upon by the whole body, depending on the corporeal and material nature for one element of perception, so that perception requires both body and mind. But it is to the rational element that the name of "soul" properly belongs: the nutritive and sensible faculties only borrow the name from that which is higher than themselves. Man was first made "in the image of God:" and this conception excludes the idea of distinction of sex. In the first creation of man all humanity is included, according to the Divine foreknowledge: "our whole nature extending from the first to the last" is "one image of Him Who is." But for the Fall, the increase of the human race would have taken place as the increase of the angelic race takes place, in some way unknown to us. The declension of man from his first estate made succession by generation necessary: and it was because this declension and its consequences were present to the Divine mind that God "created them male and female." In this respect, and in respect of the need of nourishment by food, man is not "in the image of God," but shows his kindred with the lower creation. But these necessities are not permanent: they will end with the restoration of man to his former excellence (chs. 16-18). Here Gregory is led to speak (chs. 19-20) of the food of man in Paradise, and of the "tree of the knowledge of good and evil." And thus, having made mention of the Fall of man, he goes on to speak of his Restoration. This, in his view, follows from the finite nature of evil: it is deferred until the sum of humanity is complete. As to the mode in which the present state of things will end, we know nothing: but that it will end is inferred from the non-eternity of matter (chs. 21-24). The doctrine of the Resurrection is supported by our knowledge of the accuracy with which other events have been predicted in Scripture, by the experience given to us of like events in particular cases, in those whom our Lord raised to life, and especially in His own resurrection. The argument that such a restoration is impossible is met by an appeal to the unlimited character of the Divine power, and by inferences from parallels observed in nature (chs. 25-27). Gregory then proceeds to deal with the question of the pre-existence of the soul, rejecting that opinion, and maintaining that the body and the soul come into existence together, potentially in the Divine will, actually at the moment when each individual man comes into being by generation (chs. 28-29). In the course of his argument on this last point, he turns aside to discuss at some length, in the last chapter, the structure of the human body: but he returns once more, in conclusion, to his main position, that man "is generated as a living and animated being," and that the power of the soul is gradually manifested in, and by means of, the material substratum of the body; so that man is brought to perfection by the aid of the lower attributes of the soul. But the true perfection of the soul is not in these, which will ultimately be "put away," but in the higher attributes which constitute for man "the image of God."