Objection 1: It would seem that in Christ there was no habitual knowledge. For it has been said (Q. 9, A. 1) that the highest perfection of knowledge befitted Christ's soul. But the perfection of an actually existing knowledge is greater than that of a potentially or habitually existing knowledge. Therefore it was fitting for Him to know all things actually. Therefore He had not habitual knowledge.
Obj. 2: Further, since habits are ordained to acts, a habitual knowledge which is never reduced to act would seem useless. Now, since Christ knew all things, as was said (Q. 10, A. 2), He could not have considered all things actually, thinking over one after another, since the infinite cannot be passed over by enumeration. Therefore the habitual knowledge of certain things would have been useless to Him--which is unfitting. Therefore He had an actual and not a habitual knowledge of what He knew.
Obj. 3: Further, habitual knowledge is a perfection of the knower. But perfection is more noble than the thing perfected. If, therefore, in the soul of Christ there was any created habit of knowledge, it would follow that this created thing was nobler than the soul of Christ. Therefore there was no habitual knowledge in Christ's soul.
On the contrary, The knowledge of Christ we are now speaking about was univocal with our knowledge, even as His soul was of the same species as ours. But our knowledge is in the genus of habit. Therefore the knowledge of Christ was habitual.
I answer that, As stated above (A. 4), the mode of the knowledge impressed on the soul of Christ befitted the subject receiving it. For the received is in the recipient after the mode of the recipient. Now the connatural mode of the human soul is that it should understand sometimes actually, and sometimes potentially. But the medium between a pure power and a completed act is a habit: and extremes and medium are of the same genus. Thus it is plain that it is the connatural mode of the human soul to receive knowledge as a habit. Hence it must be said that the knowledge imprinted on the soul of Christ was habitual, for He could use it when He pleased.
Reply Obj. 1: In Christ's soul there was a twofold knowledge--each most perfect of its kind: the first exceeding the mode of human nature, as by it He saw the Essence of God, and other things in It, and this was the most perfect, simply. Nor was this knowledge habitual, but actual with respect to everything He knew in this way. But the second knowledge was in Christ in a manner proportioned to human nature, i.e. inasmuch as He knew things by species divinely imprinted upon Him, and of this knowledge we are now speaking. Now this knowledge was not most perfect, simply, but merely in the genus of human knowledge; hence it did not behoove it to be always in act.
Reply Obj. 2: Habits are reduced to act by the command of the will, since a habit is that "with which we act when we wish." Now the will is indeterminate in regard to infinite things. Yet it is not useless, even when it does not actually tend to all; provided it actually tends to everything in fitting place and time. And hence neither is a habit useless, even if all that it extends to is not reduced to act; provided that that which befits the due end of the will be reduced to act according as the matter in hand and the time require.
Reply Obj. 3: Goodness and being are taken in two ways: First, simply; and thus a substance, which subsists in its being and goodness, is a good and a being; secondly, being and goodness are taken relatively, and in this way an accident is a being and a good, not that it has being and goodness, but that its subject is a being and a good. And hence habitual knowledge is not simply better or more excellent than the soul of Christ; but relatively, since the whole goodness of habitual knowledge is added to the goodness of the subject.