lent revelation was made to Isaac, being founded
on that which was made to Abraham. Wherefore it was said to him (Gen.
26:24): "I am the God of Abraham thy father," and in like manner to
Jacob (Gen. 28:13): "I am the God of Abraham thy father, and the God
of Isaac." Again in the state of the Law the first revelation which
was given to Moses was more excellent, and on this revelation all the
other revelations to the prophets were founded. And so, too, in the
time of grace the entire faith of the Church is founded on the
revelation vouchsafed to the apostles, concerning the faith in one
God and three Persons, according to Matt. 16:18, "On this rock," i.e.
of thy confession, "I will build My Church."

As to the faith in Christ's incarnation, it is evident that the
nearer men were to Christ, whether before or after Him, the more
fully, for the most part, were they instructed on this point, and
after Him more fully than before, as the Apostle declares (Eph. 3:5).

As regards the guidance of human acts, the prophetic revelation
varied not according to the course of time, but according as
circumstances required, because as it is written (Prov. 29:18), "When
prophecy shall fail, the people shall be scattered abroad." Wherefore
at all times men were divinely instructed about what they were to do,
according as it was expedient for the spiritual welfare of the elect.

Reply Obj. 1: The saying of Gregory is to be referred to the time
before Christ's incarnation, as regards the knowledge of this mystery.

Reply Obj. 2: As Augustine says (De Civ. Dei xviii, 27), "just as in
the early days of the Assyrian kingdom promises were made most
explicitly to Abraham, so at the outset of the western Babylon,"
which is Rome, "and under its sway Christ was to come, in Whom were
to be fulfilled the promises made through the prophetic oracles
testifying in word and writing to that great event to come," the
promises, namely, which were made to Abraham. "For while prophets
were scarcely ever lacking to the people of Israel from the time that
they began to have kings, it was exclusively for their benefit, not
for that of the nations. But when those prophetic writings were being
set up with greater publicity, which at some future time were to
benefit the nations, it was fitting to begin when this city," Rome to
wit, "was being built, which was to govern the nations."

The reason why it behooved that nation to have a number of prophets
especially