rk of distinction and adornment to
give forms to the elements that pre-exist.

But the belief that the firmament was made, as to its substance, on
the second day is incompatible with the opinion of Plato, according to
whom the making of the firmament implies the production of the element
of fire. This production, however, belongs to the work of creation, at
least, according to those who hold that formlessness of matter
preceded in time its formation, since the first form received by
matter is the elemental.

Still less compatible with the belief that the substance of the
firmament was produced on the second day is the opinion of Aristotle,
seeing that the mention of days denotes succession of time, whereas
the firmament, being naturally incorruptible, is of a matter not
susceptible of change of form; wherefore it could not be made out of
matter existing antecedently in time.

Hence to produce the substance of the firmament belongs to the work of
creation. But its formation, in some degree, belongs to the second
day, according to both opinions: for as Dionysius says (Div. Nom. iv),
the light of the sun was without form during the first three days, and
afterwards, on the fourth day, received its form.

If, however, we take these days to denote merely sequence in the
natural order, as Augustine holds (Gen. ad lit. iv, 22,24), and not
succession in time, there is then nothing to prevent our saying,
whilst holding any one of the opinions given above, that the
substantial formation of the firmament belongs to the second day.

Another possible explanation is to understand by the firmament that
was made on the second day, not that in which the stars are set, but
the part of the atmosphere where the clouds are collected, and which
has received the name firmament from the firmness and density of the
air. "For a body is called firm," that is dense and solid, "thereby
differing from a mathematical body" as is remarked by Basil (Hom. iii
in Hexaem.). If, then, this explanation is adopted none of these
opinions will be found repugnant to reason. Augustine, in fact (Gen.
ad lit. ii, 4), recommends it thus: "I consider this view of the
question worthy of all commendation, as neither contrary to faith nor
difficult to be proved and believed."

Reply Obj. 1: According to Chrysostom (Hom. iii in Genes.), Moses
prefaces his record by speaking of the works of God collectively, in
the words, "In the beginning God created heaven and ea