The Angelic Doctor Against the Errors of the Greeks - Chapter 7

How the Father is to be understood as needing neither Son nor Holy Spirit for his perfection.

A further difficulty stems from a passage of Athanasius in his letter to Serapion, namely, that the Father “existing fully and perfectly as God in himself and of himself, without need of anyone, needs neither the Son nor the Holy Spirit”. That the Father has no need of anything is beyond doubt; in the same way neither the Son nor the Holy Spirit wants for anything. To be in need, in the proper sense of the term, is to lack something pertaining to one’s perfection; and to be in need in this sense cannot be said of the Father, or the Son, or of the Holy Spirit.

Nevertheless, the Father could not be perfect unless he had a Son, because the Father would not exist without the Son nor would God be perfect, unless he had a Word and unless he had the breath of life, as the same Athanasius says in this third discourse on the Acts of the Council of Nicaea. Speaking of the Arians who denied that the Son and Holy Spirit are consubstantial with the Father, he says: “They describe as sterile and unfruitful the nature of the Father who has given to each things its inmost nature capable of propagating in kind. And they make the Father dumb and wordless, although he gave to all rational creatures the faculty of speech. They describe the Father as dead and deprive him of a living nature,” inasmuch as they deny that the Holy Spirit is coessential with the Father. From this it is clear that the Father would not be perfect God if he did not have the Son and the Holy Spirit. The same Athanasius states in his letter to Serapion that “the Father could not create the creature except through his Word and could not communicate himself through creatures who were to be made godlike except through the Word. And similarly neither could the Son do this except in the Holy Spirit.”

It is, therfore, common to Father, Son and Holy Spirit that none of them is in need. So, too, it is common to each of them that none can be perfect God without the other two. But for this reason Athanasius specifically says of the Father that he does not need the Son or the Holy Spirit because he does not have his perfection from another, whereas the Son and Holy Spirit have their perfection from the Father. Thus, the same Athanasius in his letter to Serapion says: “Neither by reason of the Son, nor by reason of the Holy Spirit does the Father exist as God perfect and blessed. Nor has he any source before him from whom he is, nor any after him from he derives anything, that is, which would be from the Son or from the Holy Spirit.”