orly (for this belongs to
God alone), but only exteriorly by teaching or persuading. Hence
gratuitous grace embraces whatever a man needs in order to instruct
another in Divine things which are above reason. Now for this three
things are required: first, a man must possess the fullness of
knowledge of Divine things, so as to be capable of teaching others.
Secondly, he must be able to confirm or prove what he says, otherwise
his words would have no weight. Thirdly, he must be capable of
fittingly presenting to his hearers what he knows.

Now as regards the first, three things are necessary, as may be seen
in human teaching. For whoever would teach another in any science
must first be certain of the principles of the science, and with
regard to this there is _faith,_ which is certitude of invisible
things, the principles of Catholic doctrine. Secondly, it behooves
the teacher to know the principal conclusions of the science, and
hence we have the word of _wisdom,_ which is the knowledge of Divine
things. Thirdly, he ought to abound with examples and a knowledge of
effects, whereby at times he needs to manifest causes; and thus we
have the word of _knowledge,_ which is the knowledge of human things,
since "the invisible things of Him . . . are clearly seen, being
understood by the things that are made" (Rom. 1:20).

Now the confirmation of such things as are within reason rests upon
arguments; but the confirmation of what is above reason rests on what
is proper to the Divine power, and this in two ways: first, when the
teacher of sacred doctrine does what God alone can do, in miraculous
deeds, whether with respect to bodily health--and thus there is the
_grace of healing,_ or merely for the purpose of manifesting the
Divine power; for instance, that the sun should stand still or
darken, or that the sea should be divided--and thus there is the
_working of miracles._ Secondly, when he can manifest what God alone
can know, and these are either future contingents--and thus there is
_prophecy,_ or also the secrets of hearts--and thus there is the
_discerning of spirits._

But the capability of speaking can regard either the idiom in which a
person can be understood, and thus there is _kinds of tongues_; or it
can regard the sense of what is said, and thus there is the
_interpretation of speeches._

Reply Obj. 1: As stated above (A. 1), not all the benefits divinely
conferred upon us are called gratuitous graces, but only t