Continuing the exposition of the disputed passage, which he had begun, Ambrose brings forward four reasons why we affirm that something cannot be, and shows that the first three fail to apply to Christ, and infers that the only reason why the Son can do nothing of Himself is His Unity in Power with the Father.
49. In what sense can the Son do nothing of Himself? Let us ask what it is that He cannot do. There are many different sorts of impossibilities. One thing is naturally impossible, another is naturally possible, but impossible by reason of some weakness. Again, there are things which are rendered possible by strength, impossible by unskilfulness or weakness, of body and mind. Further, there are things which it is impossible to change, by reason of the law of an unchangeable purpose, the endurance of a firm will, and, again, faithfulness in friendship.
50. To make this clearer, let us consider the matter in the light of examples. It is impossible for a bird to pursue a course of learning in any science or become trained to any art: it is impossible for a stone to move in any direction, inasmuch as it can only be moved by the motion of another body. Of itself, then, a stone is incapable of moving, and passing from its place. Again, an eagle cannot be taught in the ways of human learning.
51. It is, to take another example, impossible for a sick man to do a strong man's work; but in this case the reason of the impossibility is of a different kind, for the man is rendered unable, by sickness, to do what he is naturally capable of doing. In this case, then, the cause of the impossibility is sickness, and this kind of impossibility is different from the first, since the man is hindered by bodily weakness from the possibility of doing.
52. Again, there is a third cause of impossibility. A man may be naturally capable, and his bodily health may allow of his doing some work, which he is yet unable to do by reason of want of skill, or because his rank in life disqualifies him; because, that is, he lacks the required learning or is a slave.
53. Which of these three different causes of impossibility, think you, which we have enumerated (setting aside the fourth) can we meetly assign to the case of the Son of God? Is He naturally insensible and immovable, like a stone? He is indeed a stone of stumbling to the wicked, a cornerstone for the faithful; but He is not insensible, upon Whom the faithful affection of sentient peoples are stayed. He is not an immovable rock, |for they drank of a Rock that followed them, and that Rock was Christ.| The work of the Father, then, is not rendered impossible to Christ by diversity of nature.
54. Perchance we may suppose some things were made impossible for Him by reason of weakness. But He was not weakly Who could heal the weaknesses of others by His word of authority. Seemed He weak when bidding the paralytic take up his bed and walk? He charged the man to perform an action of which health was the necessary condition, even whilst the patient was yet praying a remedy for his disease. Not weak was the Lord of hosts when He gave sight to the blind, made the crooked to stand upright, raised the dead to life, anticipated the effects of medicine at our prayers, and cured them that besought Him, and when to touch the fringe of His robe was to be purified.
55. Unless, peradventure, you thought it was weakness, you wretches, when you saw His wounds. Truly, they were wounds piercing His Body, but there was no weakness betokened by that wound, whence flowed the Life of all, and therefore was it that the prophet said: |By His stripes we are healed.| Was He, then, Who was not weak in the hour when He was wounded, weak in regard of His Sovereignty? How, then, I ask? When He commanded the devils, and forgave the offences of sinners? Or when He made entreaty to the Father?
56. Here, indeed, our adversaries may perchance enquire: |How can the Father and the Son be One, if the Son at one time commands, at another entreats?| True, They are One; true also, He both commands and prays: yet whilst in the hour when He commands He is not alone, so also in the hour of prayer He is not weak. He is not alone, for whatsoever things the Father doeth, the same things doeth the Son also, in like manner. He is not weak, for though in the flesh He suffered weakness for our sins yet that was the chastisement of our peace upon Him, not lack of sovereign Power in Himself.
57. Moreover, that thou mayest know that it is after His Manhood that He entreats, and in virtue of His Godhead that He commands, it is written for thee in the Gospel that He said to Peter: |I have prayed for thee, that thy faith fail not.| To the same Apostle, again, when on a former occasion he said, |Thou art the Christ, the Son of the living God,| He made answer: |Thou art Peter, and upon this Rock will I build My Church, and I will give thee the keys of the kingdom of heaven.| Could He not, then, strengthen the faith of the man to whom, acting on His own authority, He gave the kingdom, whom He called the Rock, thereby declaring him to be the foundation of the Church? Consider, then, the manner of His entreaty, the occasions of His commanding. He entreats, when He is shown to us as on the eve of suffering: He commands, when He is believed to be the Son of God.
58. We see, then, that two sorts of impossibility furnish no explanation, inasmuch as the Power of God can be neither insensible nor weakly. Will you then proffer the third kind [as an account of the matter], namely, that He can do nothing, just as an unskilled apprentice can do nothing without his master's instructions, or a slave can do nothing without his lord. Then didst Thou speak falsely, Lord Jesu, in calling Thyself Master and Lord, and Thou didst deceive Thy disciples by Thy words: |Ye call Me Master and Lord, and ye say well, for so I am.| Nay, but Thou, O Truth, wouldst never have deceived men, least of all them whom Thou didst call friends.
59. Yet if our enemies sunder Thee from the Creator, as being unskilled, let them see how they affirm that skill was lacking to Thee, that is to say, to the Divine Wisdom; for all that, however, they cannot divide the unity of substance that Thou hast with the Father. It is not, indeed, by nature, but by reason of ignorance, that the difference exists between the craftsman and the unskilled; but neither is handicraft attributable to the Father, nor ignorance to Thee, for there is no such thing as ignorant wisdom.
60. Therefore, if insensibility is no attribute of the Son, and if neither weakness, nor ignorance, nor servility, let unbelievers put it to their minds for meditation that both by nature and sovereignty the Son is One with the Father, and by its working His power is not at cross-purpose with the Father, inasmuch as |all things that the Father hath done, the Son doeth likewise,| for no one can do in like fashion the same work that another has done, unless he shares in the unity of the same nature, whilst he is also not inferior in method of working.
61. Yet I would still enquire what it is that the Son cannot do, unless He see the Father doing it. I will take the fool's line, and propound some examples drawn from things of a lower world. |I am become a fool; ye have compelled me.| What indeed is more foolish than to debate over the majesty of God, which rather occasions questionings, than godly instruction which is in faith. But to arguments let arguments reply; let words make answer to them, but love to us, the love which is in God, issuing of a pure heart and good conscience and faith unfeigned. And so I stickle not to introduce even the ludicrous for the confutation of so vain a thesis.
62. How, then, does the Son see the Father? A horse sees a painting, which naturally it is unable to imitate. Not thus does the Son behold the Father. A child sees the work of a grown man, but he cannot reproduce it; certainly not thus, again, does the Son see the Father.
63. If, then, the Son can, by virtue of a common hidden power of the same nature which He has with the Father, both see and act in an invisible manner, and by the fulness of His Godhead execute every decree of His Will, what remains for us but to believe that the Son, by reason of indivisible unity of power, does nothing, save what He has seen the Father doing, forasmuch as because of His incomparable love the Son does nothing of Himself, since He wills nothing that is against His Father's Will? Which truly is the proof not of weakness but of unity.