69. Therefore amid the numerous dangers which
threaten the faith, brevity of words must be employed sparingly, lest
what is piously meant be thought to be impiously expressed, and a word
be judged guilty of occasioning heresy when it has been used in
conscientious and unsuspecting innocence. A Catholic about to
state that the substance of the Father and the Son is one, must not
begin at that point: nor hold this word all important as though
true faith did not exist where the word was not used. He will be
safe in asserting the one substance if he has first said that the
Father is unbegotten, that the Son is born, that He draws His personal
subsistence from the Father, that He is like the Father in might,
honour and nature, that He is subject to the Father as to the Author of
His being, that He did not commit robbery by making Himself equal with
God, in whose form He remained, that He was obedient unto death.
He did not spring from nothing, but was born. He is not incapable
of birth but equally eternal. He is not the Father, but the Son
begotten of Him. He is not any portion of God, but is whole
God. He is not Himself the source but the image; the image of God
born of God to be God. He is not a creature but is God. Not
another God in the kind of His substance, but the one God in virtue of
the essence of His exactly similar substance. God is not one in
Person but in nature, for the Born and the Begetter have nothing
different or unlike. After saying all this, he does not err in
declaring one substance of the Father and the Son. Nay, if he now
denies the one substance he sins.