When therefore He had furnished his nature with
free-will, He imposed a law on him, not to taste of the tree of
knowledge. Concerning this tree, we have said as much as is
necessary in the chapter about Paradise, at least as much as it was in
our power to say. And with this command He gave the promise that,
if he should preserve the dignity of the soul by giving the victory to
reason, and acknowledging his Creator and observing His command, he
should share eternal blessedness and live to all eternity, proving
mightier than death: but if forsooth he should subject the soul
to the body, and prefer the delights of the body, comparing himself in
ignorance of his true dignity to the senseless beasts Ps. xlix. 12., and shaking off His Creator’s yoke,
and neglecting His divine injunction, he will be liable to death and
corruption, and will be compelled to labour throughout a miserable
life. For it was no profit to man to obtain incorruption while
still untried and unproved, lest he should fall into pride and under
the judgment of the devil. For through his incorruption the
devil, when he had fallen as the result of his own free choice, was
firmly established in wickedness, so that there was no room for
repentance and no hope of change: just as, moreover, the angels
also, when they had made free choice of virtue became through grace
immoveably rooted in goodness.