The Angelic Doctor Against the Errors of the Greeks - Chapter 4

 How the essence is to understood as begotten in the Son and spirated in the Holy Spirit.

Among the sayings of the aforesaid Fathers  is met the assertion that the essence is begotten in the Son and spirated in the Holy Spirit. For Athanasius in his third discourse on the Acts of the Council of Nicaea, speaking in the person of the Son, says: “I distribute to men your Spirit together with the divine essence begotten of you.” And a little further on: “From your essence which you have begotten in me I give the Holy Spirit to them.”  The same Father writes in his letter to Serapion: “The Parent himself keeping in himself his essence ineffably begot it whole and entire in his Son.”  And again: “As the Father has life in himself, that is, a living spirating nature, so he has given to the Son to have life in himself, that is, he begot in the Son the same nature spirating a living Spirit.” Subsequently he says of the Father and Son “that the deity is one naturally spirating one Holy Spirit.”  From these passages it follows that in the Son the divine nature spirates the Holy Spirit.

Cyril in his Thesaurus against the heretics states: “The power, uncreated and begotten in the Son, pertains to the Son according to every modality of the Son’s nature.” And again: “The Father gives life to the Son, that is, he begot his natural life in the Son.”  And Basil says: “The Son himself whom the Father gives us is God in essence begotten of God, having in himself the whole essence of the Father as begotten.”  Athanasius likewise asserts in his letter to Serapion that the divine essence in the Holy Spirit is spirated. He says: “The Holy Spirit is the true and natural image of the Son in virtue of the essence wholly spirated into him by the same.” 

This manner of speaking, however, is highly misleading, and at the [Fourth] Lateran Council  the teaching of Joachim, who presumptuously defended it against Master Peter Lombard, was condemned. In the 5 ^th distinction of his First Book of the Sentences  the aforementioned Master Peter shows that the common essence does not beget, is not begotten, and does not proceed; this is because in God there is a common element indistinct and one which is distinguished and not common. Therefore, that which is the ground of distinction in God cannot be attributed to what is common and indistinct, but only to that which is distinguished. There is, however, no other ground of distinction in God but this: that one person begets, another is begotten, and another proceeds. Therefore, to beget or to be begottten or to proceed cannot be attributed to the divine essence, which is common and indistinct in the three persons. What is distinct in God, however, is the person or hypostasis or supposit of the divine nature, i.e., what has the divine nature. Hence, those terms which signify or can stand for a person receive the appropriate predication of generation or procession. Thus, these terms: Father, Son and Holy Spirit, connote specific persons, while this term: person, or hypostasis, connotes them generically. Hence, it is proper to say that the Father begets the Son, and that the Son is begotten of the Father and that the Holy Spirit proceeds from the Father and the Son, and also that a person begets or spirates a person, or is begotten or spirated by a person.

The term God, however, because it signifies the divine essence as existing concretely—for it signifies someone who possesses divinity—can, therefore, because of its manner of signifying, stand for a person and so the following ways of speaking are properly permitted: God begets God; God is begotten or proceeds from God.

But the terms essence and divinity and any other connoting abstractly cannot by reason of their mode of signifying signify or stand for a person. And so, personal properties cannot rightly be predicated of the essence or of the godhead, for instance, the essence begets or is begotten. Some of these terms, however, are more closely linked to the personal, inasmuch as they signify principles of acts proper to persons, e.g., light, wisdom, goodness and the like. Hence, it is less inappropriate to predicate personal properties of such, for example, the Son is light of light or wisdom of wisdom. But the phrase: essence of essence, entails greater difficulty.

Although the mode of signifying is diverse in the case of the terms God and deity, the reality to which they refer is absolutely the same. And therefore, just as by reason of that identical reality one is predicated of the other, as when God is called the deity, or a divine person or the Father the divine essence, so too from time to time the saints have used the terms interchangeably, stating, for example, that the divine essence begets because the Father who is the divine essence begets, or that the essence is from the essence because the Son who is the essence is from the Father who is the same divine essence. Cyril in his Thesaurus says: “ The Father living of himself by his own life and truly existing by his own essence, in begetting the Son as from a true root, gives him naturally his own natural life and essence.”  So when it is stated that the Father begets his own nature in the Son, this is to be interpreted as meaning that by generation he gives his own nature to the Son, as in the text of Cyril just quoted.