enters the
definition of the other. But in God the relations themselves are the
persons subsisting in one nature. So, neither on the part of the
nature, nor on the part the relations, can one person be prior to
another, not even in the order of nature and reason.

Reply Obj. 3: The order of nature means not the ordering of nature
itself, but the existence of order in the divine Persons according to
natural origin.

Reply Obj. 4: Nature in a certain way implies the idea of a
principle, but essence does not; and so the order of origin is more
correctly called the order of nature than the order of essence.
_______________________

FOURTH ARTICLE [I, Q. 4, Art. 4]

Whether the Son Is Equal to the Father in Greatness?

Objection 1: It would seem that the Son is not equal to the Father in
greatness. For He Himself said (John 14:28): "The Father is greater
than I"; and the Apostle says (1 Cor. 15:28): "The Son Himself shall
be subject to Him that put all things under Him."

Obj. 2: Further, paternity is part of the Father's dignity. But
paternity does not belong to the Son. Therefore the Son does not
possess all the Father's dignity; and so He is not equal in greatness
to the Father.

Obj. 3: Further, wherever there exist a whole and a part, many parts
are more than one only, or than fewer parts; as three men are more
than two, or than one. But in God a universal whole exists, and a
part; for under relation or notion, several notions are included.
Therefore, since in the Father there are three notions, while in the
Son there are only two, the Son is evidently not equal to the Father.

_On the contrary,_ It is said (Phil. 2:6): "He thought it not robbery
to be equal with God."

_I answer that,_ The Son is necessarily equal to the Father in
greatness. For the greatness of God is nothing but the perfection of
His nature. Now it belongs to the very nature of paternity and
filiation that the Son by generation should attain to the possession
of the perfection of the nature which is in the Father, in the same
way as it is in the Father Himself. But since in men generation is a
certain kind of transmutation of one proceeding from potentiality to
act, it follows that a man is not equal at first to the father who
begets him, but attains to equality by due growth, unless owing to a
defect in the principle of generation it should happen otherwise.
From what precedes (Q. 27, A. 2; Q. 33, AA. 2 ,3), it is evident that
in God t