Of the Person of the Father
Of the Person of the Father — St. Thomas Aquinas asks: Whether it belongs to the Father to be the principle?; Whether this name "Father" is properly the name of a divine person?; Whether this name "Father" is applied to God, firstly as a personal name?; Whether it is proper to the Father to be unbegotten?.
We now consider the persons singly; and first, the Person of the Father, concerning Whom there are four points of inquiry:
Article 1: Whether it belongs to the Father to be the principle?
Augustine says (De Trin. iv, 20), "The Father is the Principle of the whole Deity."
The word "principle" signifies only that whence another proceeds: since anything whence something proceeds in any way we call a principle; and conversely. As the Father then is the one whence another proceeds, it follows that the Father is a principle.
Article 2: Whether this name "Father" is properly the name of a divine person?
It is said (Ps. 88:27): "He shall cry out to me: Thou art my Father."
The proper name of any person signifies that whereby the person is distinguished from all other persons. For as body and soul belong to the nature of man, so to the concept of this particular man belong this particular soul and this particular body; and by these is this particular man distinguished from all other men. Now it is paternity which distinguishes the person of the Father from all other persons. Hence this name "Father," whereby paternity is signified, is the proper name of the person of the Father.
Article 3: Whether this name "Father" is applied to God, firstly as a personal name?
The eternal comes before the temporal. But God is the Father of the Son from eternity; while He is the Father of the creature in time. Therefore paternity in God is taken in a personal sense as regards the Son, before it is so taken as regards the creature.
A name is applied to that wherein is perfectly contained its whole signification, before it is applied to that which only partially contains it; for the latter bears the name by reason of a kind of similitude to that which answers perfectly to the signification of the name; since all imperfect things are taken from perfect things. Hence this name "lion" is applied first to the animal containing the whole nature of a lion, and which is properly so called, before it is applied to a man who shows something of a lion's nature, as courage, or strength, or the like; and of whom it is said by way of similitude.
Now it is manifest from the foregoing (; ), that the perfect idea of paternity and filiation is to be found in God the Father, and in God the Son, because one is the nature and glory of the Father and the Son. But in the creature, filiation is found in relation to God, not in a perfect manner, since the Creator and the creature have not the same nature; but by way of a certain likeness, which is the more perfect the nearer we approach to the true idea of filiation. For God is called the Father of some creatures, by reason only of a trace, for instance of irrational creatures, according to Job 38:28: "Who is the father of the rain? or who begot the drops of dew?" Of some, namely, the rational creature (He is the Father), by reason of the likeness of His image, according to Dt. 32:6: "Is He not thy Father, who possessed, and made, and created thee?" And of others He is the Father by similitude of grace, and these are also called adoptive sons, as ordained to the heritage of eternal glory by the gift of grace which they have received, according to Rom. 8:16,17: "The Spirit Himself gives testimony to our spirit that we are the sons of God; and if sons, heirs also." Lastly, He is the Father of others by similitude of glory, forasmuch as they have obtained possession of the heritage of glory, according to Rom. 5:2: "We glory in the hope of the glory of the sons of God." Therefore it is plain that "paternity" is applied to God first, as importing regard of one Person to another Person, before it imports the regard of God to creatures.
Article 4: Whether it is proper to the Father to be unbegotten?
Hilary says (De Trin. iv): "One is from one ---that is, the Begotten is from the Unbegotten---namely, by the property in each one respectively of innascibility and origin."
As in creatures there exist a first and a secondary principle, so also in the divine Persons, in Whom there is no before or after, is formed the principle not from a principle, Who is the Father; and the principle from a principle, Who is the Son.
Now in things created a first principle is known in two ways; in one way as the first "principle," by reason of its having a relation to what proceeds from itself; in another way, inasmuch as it is a "first" principle by reason of its not being from another. Thus therefore the Father is known both by paternity and by common spiration, as regards the persons proceeding from Himself. But as the principle, not from a principle He is known by the fact that He is not from another; and this belongs to the property of innascibility, signified by this word "begotten."