s the first place.

Reply Obj. 2: In the opinion of some the light here spoken of was a
kind of luminous nebula, and that on the making of the sun this
returned to the matter of which it had been formed. But this cannot
well be maintained, as in the beginning of Genesis Holy Scripture
records the institution of that order of nature which henceforth is
to endure. We cannot, then, say that what was made at that time
afterwards ceased to exist.

Others, therefore, held that this luminous nebula continues in
existence, but so closely attached to the sun as to be
indistinguishable. But this is as much as to say that it is
superfluous, whereas none of God's works have been made in vain. On
this account it is held by some that the sun's body was made out of
this nebula. This, too, is impossible to those at least who believe
that the sun is different in its nature from the four elements, and
naturally incorruptible. For in that case its matter cannot take on
another form.

I answer, then, with Dionysius (Div. Nom. iv), that the light was the
sun's light, formless as yet, being already the solar substance, and
possessing illuminative power in a general way, to which was
afterwards added the special and determinative power required to
produce determinate effects. Thus, then, in the production of this
light a triple distinction was made between light and darkness.
First, as to the cause, forasmuch as in the substance of the sun we
have the cause of light, and in the opaque nature of the earth the
cause of darkness. Secondly, as to place, for in one hemisphere there
was light, in the other darkness. Thirdly, as to time; because there
was light for one and darkness for another in the same hemisphere;
and this is signified by the words, "He called the light day, and the
darkness night."

Reply Obj. 3: Basil says (Hom. ii in Hexaem.) that day and night were
then caused by expansion and contraction of light, rather than by
movement. But Augustine objects to this (Gen. ad lit. i), that there
was no reason for this vicissitude of expansion and contraction since
there were neither men nor animals on the earth at that time, for
whose service this was required. Nor does the nature of a luminous
body seem to admit of the withdrawal of light, so long as the body is
actually present; though this might be effected by a miracle. As to
this, however, Augustine remarks (Gen. ad lit. i) that in the first
founding of the order of nature we mus