CHAPTER XLIV—That the Human Nature, assumed by the Word, was perfect in Soul and Body in the instant of Conception

THE Word of God took a body through the medium of a rational soul: for the body of man is not more assumable by God than other bodies except for the rational soul.⁹⁴¹⁹⁴¹St Gregory Nazianzen in his poem Against Apollinaris, 50 sq., asks how two things so far apart as Deity and humanity could be united, and replies: ‘Tis mystery, I but conjecture make. Divinity with flesh unmeet to blend: But thinking Soul, as ‘twere a frontier power, Image of God, in body domiciled, Is apt to mediate between the twain. The Godhead then conjoined itself with Soul, And so assumed dimensions of a man. The Word of God then did not assume a body without a rational soul. Since then the Word of God assumed a body from the first instant of conception, in that very instant the rational soul must have been united with the body.

4. The body which the Word assumed was formed from the first instant of conception, because it would have been against the fitness of things for the Word of God to have assumed anything that was formless. Moreover the soul, like any other natural form, requires its proper matter. Now the proper matter of the soul is an organised body: for “the soul is the actualisation of an organic, natural body, that is in potentiality to life.”⁹⁴²⁹⁴²Aristotle, De anima, I, ii. If then the soul was united with the body from the first instant of conception, the body must needs have been organised and formed from the first instant of conception. Moreover in the order of the stages of generation the organisation of the body precedes the introduction of the rational soul: hence, positing the latter, we must posit the former stage also. But increase in quantity up to the due measure may very well be subsequent to the animation of the body. Thus then, concerning the conception of the Man assumed, we must think that in the very instant of conception His body was organised and formed, but had not as yet its due quantity.⁹⁴³⁹⁴³   The links of St Thomas’s argument are these:
   (a) The Word was made flesh the very instant that His Humanity was conceived, the very instant that Mary spoke the word: Be it done to me according to thy word.
   (b) The Word would not take flesh otherwise than by assuming a body there and then animated with a rational soul.
   (c) A rational soul cannot inform a body not yet developed to human shape. In the ordinary course of human embryonic development, the embryo at conception, being incapable even of a sentient, still more of a rational soul, is animated with a vegetative soul, which after some days gives place to a sentient soul, and that after more days are expired, and the foetus is come to human shape, is finally replaced by a rational soul: all which process is drawn out at length in B. II, Chapp. LXXXVIII, LXXXIX.
   (d) This ordinary process of nature had to be set aside in the formation of Mary’s miraculous Child. His Body was complete from the first, a fit receptacle for a rational soul. His Body consequently did not develop, it simply grew.
   Now the link (c) of this chain is broken by modern Catholic theologians. They see no difficulty in a rational soul informing a body not yet developed to human shape. They hold that the rational soul is always infused in the very instant of conception. Thereupon they conclude that the way of formation of Christ’s body, after conception, in no way differed from that of other human bodies, nihil differens fuisse a reliquis foetibus humanis (Pesch, Praelectiones Dogmaticae, vol. IV, p. 85, ed. 1896).
   Scripture is silent on the subject; modern biology would be amazed at such a mode of growth as St Thomas and Suarez after him suppose; and miracles, as Suarez himself here owns, are not to be multiplied without necessity or high congruity (Suarez, De mysteriis Christi, disp. II, sect. 2, nn. 2, 4).
   This discussion has an extrinsic interest as illustrating two several views of another mighty development, that of Church government and doctrine. The development of the Bridegroom may well be the pattern of that of the Bride.
   Accepting St Thomas’s supposition of the three successive souls, as a supposition not yet quite exploded, there is still some doubt as to his conclusion, in point of link (b). The Word remained united with the dead Body of Christ, from whence all soul was departed: might it not then unite itself with a living Body into which in due course of nature a rational soul was soon to come?