I answer that, Acquired knowledge is held to be in Christ's soul, as we have said (Q. 9, A. 4), by reason of the active intellect, lest its action, which is to make things actually intelligible, should be wanting; even as imprinted or infused knowledge is held to be in Christ's soul for the perfection of the passive intellect. Now as the passive intellect is that by which "all things are in potentiality," so the active intellect is that by which "all are in act," as is said De Anima iii, 18. And hence, as the soul of Christ knew by infused knowledge all things to which the passive intellect is in any way in potentiality, so by acquired knowledge it knew whatever can be known by the action of the active intellect.
Reply Obj. 1: The knowledge of things may be acquired not merely by experiencing the things themselves, but by experiencing other things; since by virtue of the light of the active intellect man can go on to understand effects from causes, and causes from effects, like from like, contrary from contrary. Therefore Christ, though He did not experience all things, came to the knowledge of all things from what He did experience.
Reply Obj. 2: Although all sensible things were not subjected to Christ's bodily senses, yet other sensible things were subjected to His senses; and from this He could come to know other things by the most excellent force of His reason, in the manner described in the previous reply; just as in seeing heavenly bodies He could comprehend their powers and the effects they have upon things here below, which were not subjected to His senses; and for the same reason, from any other things whatsoever, He could come to the knowledge of yet other things.
Reply Obj. 3: By this knowledge the soul of Christ did not know all things simply, but all such as are knowable by the light of man's active intellect. Hence by this knowledge He did not know the essences of separate substances, nor past, present, or future singulars, which, nevertheless, He knew by infused knowledge, as was said above (Q. 11). _______________________
SECOND ARTICLE [III, Q. 12, Art. 2]
Whether Christ Advanced in Acquired or Empiric Knowledge?
Objection 1: It would seem that Christ did not advance in this knowledge. For even as Christ knew all things by His beatific and His infused knowledge, so also did He by this acquired knowledge, as is plain from what has been said (A. 1). But He did not advance in these knowledges. Therefore neither in this.
Obj. 2: Further, to advance belongs to the imperfect, since the perfect cannot be added to. Now we cannot suppose an imperfect knowledge in Christ. Therefore Christ did not advance in this knowledge.
Obj. 3: Further, Damascene says (De Fide Orth. iii, 22): "Whoever say that Christ advanced in wisdom and grace, as if receiving additional sensations, do not venerate the union which is in hypostasis." But it is impious not to venerate this union. Therefore it is impious to say that His knowledge received increase.
On the contrary, It is written (Luke 2:52): "Jesus advanced in wisdom and age and grace with God and men"; and Ambrose says (De Incar. Dom. vii) that "He advanced in human wisdom." Now human wisdom is that which is acquired in a human manner, i.e. by the light of the active intellect. Therefore Christ advanced in this knowledge.