What follows begins with St Thomas’ brief teaching on this question as found in his COMPENDIUM OF THEOLOGY; after which, one will find the corresponding teaching
from The SUMMA THEOLOGICA. You may wish to consider reading only the bold text of the SUMMA article. Notes and links for further study ma also be provided.
(Note: Science, as St Thomas uses it, refers to knowledge-”scientia”- a developed body of knowledge based on causes or general principles)
COMPENDIUM:
this docttrine is a sceince proceeding from principles made known by the light of a higher science, as music proceeds from principles explained by mathematics.
For Sacred Doctrine proceeds from principles made know by the light of a higher knowledge, that is to say, the Divine Knowledge, and in certain particulars are
treated of, both as an example of life and in order thea we may know clearly by what instrumentality this revelation is made.
Whether Sacred Doctrine Is a Science?
Objection 1: It seems that sacred doctrine is not a science. For every
science proceeds from self-evident principles. But sacred doctrine
proceeds from articles of faith which are not self-evident, since
their truth is not admitted by all: “For all men have not faith” (2
Thess. 3:2). Therefore sacred doctrine is not a science.
Obj. 2: Further, no science deals with individual facts. But this
sacred science treats of individual facts, such as the deeds of
Abraham, Isaac and Jacob and such like. Therefore sacred doctrine is
not a science.
_On the contrary,_ Augustine says (De Trin. xiv, 1) “to this science
alone belongs that whereby saving faith is begotten, nourished,
protected and strengthened.” But this can be said of no science except
sacred doctrine. Therefore sacred doctrine is a science.
_I answer that,_ Sacred doctrine is a science. We must bear in mind that
there are two kinds of sciences. There are some which proceed from a
principle known by the natural light of intelligence, such as
arithmetic and geometry and the like. There are some which proceed
from principles known by the light of a higher science: thus the
science of perspective proceeds from principles established by
geometry, and music from principles established by arithmetic. So it
is that sacred doctrine is a science because it proceeds from
principles established by the light of a higher science, namely, the
science of God and the blessed. Hence, just as the musician accepts on
authority the principles taught him by the mathematician, so sacred
science is established on principles revealed by God.
Reply Obj. 1: The principles of any science are either in
themselves self-evident, or reducible to the conclusions of a higher
science; and such, as we have said, are the principles of sacred
doctrine.
Reply Obj. 2: Individual facts are treated of in sacred
doctrine, not because it is concerned with them principally, but they
are introduced rather both as examples to be followed in our lives (as
in moral sciences) and in order to establish the authority of those
men through whom the divine revelation, on which this sacred scripture
or doctrine is based, has come down to us.
For a very good, brief summary of the teaching given here, please see Alfred J Freddoso’s comments.
Brandon as SIRIS has more on this article and others related to Q. 1 of the Summa’s first part.
THE 60-SECOND AQUINAS LESSON, which, sadly, is no longer updated, notes the importance of this article for Thomas’ later treatment of the intellectual virtues.
