Reply to Objection 2: According to some, knowledge and active power are not in the same ratio; for an active power flows from the very nature of the thing, inasmuch as action is considered to come forth from the agent; but knowledge is not always possessed by the very essence or form of the knower, since it may be had by assimilation of the knower to the thing known by the aid of received species. But this reason seems not to suffice, because even as we may understand by a likeness obtained from another, so also may we act by a form obtained from another, as water or iron heats, by heat borrowed from fire. Hence there would be no reason why the soul of Christ, as it can know all things by the similitudes of all things impressed upon it by God, cannot do these things by the same similitudes.
It has, therefore, to be further considered that what is received in the lower nature from the higher is possessed in an inferior manner; for heat is not received by water in the perfection and strength it had in fire. Therefore, since the soul of Christ is of an inferior nature to the Divine Nature, the similitudes of things are not received in the soul of Christ in the perfection and strength they had in the Divine Nature. And hence it is that the knowledge of Christ's soul is inferior to Divine knowledge as regards the manner of knowing, for God knows (things) more perfectly than the soul of Christ; and also as regards the number of things known, since the soul of Christ does not know all that God can do, and these God knows by the knowledge of simple intelligence; although it knows all things present, past, and future, which God knows by the knowledge of vision. So, too, the similitudes of things infused into Christ's soul do not equal the Divine power in acting, i.e. so as to do all that God can do, or to do in the same manner as God does, Who acts with an infinite might whereof the creature is not capable. Now there is no thing, to know which in some way an infinite power is needed, although a certain kind of knowledge belongs to an infinite power; yet there are things which can be done only by an infinite power, as creation and the like, as is plain from what has been said in the FP, Question [45]. Hence Christ's soul which, being a creature, is finite in might, can know, indeed, all things, but not in every way; yet it cannot do all things, which pertains to the nature of omnipotence; and, amongst other things, it is clear it cannot create itself.