ll the chief heretics of his
time. His twelve books against Eunomius, were ever most justly valued
above the rest. St. Basil had refuted that heresiarch's apology; nor
durst he publish any answer till after the death of that eloquent
champion of the faith. Then the Apology of his Apology began to creep
privately abroad. St. Gregory got at last a copy, and wrote his twelve
excellent books, in which he vindicates St. Basil's memory, and gives
many secret histories of the base Eunomius's life. He proves against him
the Divinity and Consubstantiality of God the Son. Though he employs the
scripture with extraordinary sagacity, he says, tradition, by succession
from the apostles, is alone sufficient to condemn heretics. (Or. 3,
contra Eunom. p. 123.) We have his treatise To Ablavius, that there are
not three gods. A treatise On Faith also against the Arians. That On
Common Notions is an explication of the terms used about the Blessed
Trinity. We have his Ten Syllogisms against the Manichees, proving that
evil cannot be a God. The heresy {557} of the Apollinarists beginning to
be broached, St. Gregory wrote to Theophilus patriarch of Alexandria,
against them, showing there is but one Person in Christ. But his great
work against Apollinaris is his Antirretic, quoted by Leontius, the
sixth general council, &c. Only a fragment was printed in the edition of
this father's works; but it was published from MSS. by Zacagnius,
prefect of the Vatican Library, in 1698. He shows in it that the
Divinity could not suffer, and that there must be two natures in Christ,
who was perfect God and perfect man. He proves also, against
Apollinaris, that Christ had a human soul with a human understanding.
His book of Testimonies against the Jews is another fruit of his zeal.

St. Gregory so clearly establishes the Procession of the Holy Ghost from
the Son, that some Greeks, obstinate in that heresy, erased out of his
writings the words _out of_, as they confessed in a council at
Constantinople, in 1280. He expressly condemned Nestorianism before it
was broached, and says, "No one dare call the holy Virgin and mother of
God, mother of man." (Ep. ad Eustath. p. 1093.) He asserts her virginity
in and after the birth of Christ. (Or. contr. Ennom. p. 108, and Serm.
in natale Christi, p. 776.) He is no less clear for transubstantiation
in his great catechistical discourse (c. 37, pp. 534, 535,) for the
sacrifice and the altar. Or in Bapt. Christi, p. 801. P