first perfection is the cause of the second, as
above said. Now for the attaining of beatitude two things are
required, nature and grace. Therefore, as said above, the perfection
of beatitude will be at the end of the world. But this consummation
existed previously in its causes, as to nature, at the first founding
of the world, as to grace, in the Incarnation of Christ. For, "Grace
and truth came by Jesus Christ" (John 1:17). So, then, on the seventh
day was the consummation of nature, in Christ's Incarnation the
consummation of grace, and at the end of the world will be the
consummation of glory.

Reply Obj. 2: God did act on the seventh day, not by creating new
creatures, but by directing and moving His creatures to the work
proper to them, and thus He made some beginning of the _second_
perfection. So that, according to our version of the Scripture, the
completion of the works is attributed to the seventh day, though
according to another it is assigned to the sixth. Either version,
however, may stand, since the completion of the universe as to the
completeness of its parts belongs to the sixth day, but its
completion as regards their operation, to the seventh. It may also be
added that in continuous movement, so long as any movement further is
possible, movement cannot be called completed till it comes to rest,
for rest denotes consummation of movement. Now God might have made
many other creatures besides those which He made in the six days, and
hence, by the fact that He ceased making them on the seventh day, He
is said on that day to have consummated His work.

Reply Obj. 3: Nothing entirely new was afterwards made by God, but
all things subsequently made had in a sense been made before in the
work of the six days. Some things, indeed, had a previous experience
materially, as the rib from the side of Adam out of which God formed
Eve; whilst others existed not only in matter but also in their
causes, as those individual creatures that are now generated existed
in the first of their kind. Species, also, that are new, if any such
appear, existed beforehand in various active powers; so that animals,
and perhaps even new species of animals, are produced by putrefaction
by the power which the stars and elements received at the beginning.
Again, animals of new kinds arise occasionally from the connection of
individuals belonging to different species, as the mule is the
offspring of an ass and a mare; but even these ex