Without an understanding of Aristotelian psychology, the following will be difficult to follow. A grasp of Aristotle’s de Anima (On the Soul), especially as regards the intellect and the process of coming to knowledge of the external world, should be had if one expects to understand the terminology employed by Thomas.
Does Christ know all things by this knowledge?
The knowledge of all Divine things belongs to wisdom, the knowledge of all immaterial things to understanding, the knowledge of all conclusions to knowledge [scientia], the knowledge of all practical things to counsel. Christ had the knowledge of all things.
As was said above (Question 9, Article 1), it was fitting that the soul of Christ should be wholly perfected by having each of its powers reduced to act. (Note: it is always good to remember that the Scholastic and philosophical term “reduce” has a very different connotation than we would apply to the word in ordinary speech, and has nothing to do with something’s lessening in a belittling way). The soul of Christ knew: First, whatever can be known by force of a man’s active intellect and secondly, by this knowledge Christ knew all things made known to man by Divine revelation. So the intellectual virtues, both acquired and infused, were in Him perfect.
Could He use this knowledge by turning to phantasms?
The soul of Christ knew certain things which could not be known by the senses, for He had the beatific vision and did not have the lack of “vision” that we have while limited by the earthly body. Therefore it could understand without turning to phantasms.
In the state before His Passion Christ was at the same time a wayfarer like and a comprehensor, having the vision of God. After the resurrection glory will flow from the soul to the body, rather than here where it seems our soul is more dependant and limited by, rather than master of, the body.
Although His soul could understand without turning to phantasms it could also understand by turning to phantasms, so His soul’s senses were not useless.
Was this knowledge collative or discursive?
Christ had a rational soul, and the proper operation of a rational soul consists in comparison and discursion from one thing to another, so He had this type of knowledge.
As is so often the case, a distinction must be made to properly understand this teaching. Knowledge may be discursive or collative in two ways. First, in the acquisition of the knowledge, as happens to us, but this is not so for Christ.
But knowledge may be called discursive or collative in use, and in this way, because of His humanity, Christ’s soul could be collative or discursive.
The comparison of this knowledge with the angelic knowledge
Because angels are pure intellect, far beyond men in vision, one must ask if Christ’s human soul had knowledge in some way less than that of angels, being a true human soul and sharing this lower nature with us. Again, the answer will depend upon an important distinction.
As regards what it has from the inflowing cause, it is more perfect than the angels, but as regards what it has from the subject receiving it (His very human soul) the knowledge imprinted on the soul of Christ is less than the angelic knowledge, in the manner of knowing that is natural to the human soul. This manner of knowing is by way of phantasms and then discursive reasoning, as mentioned above.
Was it a habitual knowledge?
For Thomas, the term habit goes beyond that of our current usage of the word. This is not the place to discuss it in depth, but one should know that habitus is more than mere repetition so that similar actions become simply something mechanically automatic. Likewise, an understanding of habitual knowledge, as taught by the scholastics, should be grasped. Psychologically, habit signifies the acquired facility of conscious processes.
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.
Basically, we do not want to say that Christ’s knowledge, as One with a human intellect, was merely equivocal or analogical to ours, but must be univocal; otherwise, it would not be a true human soul. As such, His soul shares in our nature, and operations go with the natures that they are attached to. Such was Christ’s knowledge.
As stated above (under Comparison of this knowledge with the angelic), 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. We have seen this phrase before and we shall see it often in the thought of Thomas. We must remember that Jesus is God, and in this respect, the giver, but also, as man, He is the receiver. We must realize that Christ is one person, but we often speak of Christ as man or as God in careful distinction.
Was it distinguished by various habits?
It is objected that in the soul of Christ there was only one habit of knowledge because the more perfect knowledge is, the more united it is, and Christ’s knowledge was most perfect and therefore one and not distinguished by several habits.
However, as stated above (4,5), the knowledge imprinted on Christ’s soul has a mode connatural to a human soul (according to the mode of the receiver). This means it won’t be received in the universal mode that angels receive knowledge, but in like manner to how we have knowledge of various things, because there are different classes of knowable things, inasmuch as what are in one genus are known by one type of habit or another.
Christ’s soul is most perfect, and exceeds the knowledge of angels with regard to what is in it on the part of God’s gift; but it is below the angelic knowledge as regards the mode of the recipient.
What is received is received according to the mode of the receiver.