Thomas Aquinas, Summa Theologiae

Objection 1: It would seem that the Son is not equal to the Father in greatness. For He Himself said (Jn. 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."

Objection 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.

Objection 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 (Question 27, Article 2; Question 33, Articles 2,3), it is evident that in God there exist real true paternity and filiation. Nor can we say that the power of generation in the Father was defective, nor that the Son of God arrived at perfection in a successive manner and by change. Therefore we must say that the Son was eternally equal to the Father in greatness. Hence, Hilary says (De Synod. Can. 27): "Remove bodily weakness, remove the beginning of conception, remove pain and all human shortcomings, then every son, by reason of his natural nativity, is the father's equal, because he has a like nature."

Reply to Objection 1: These words are to be understood of Christ's human nature, wherein He is less than the Father, and subject to Him; but in His divine nature He is equal to the Father. This is expressed by Athanasius, "Equal to the Father in His Godhead; less than the Father in humanity": and by Hilary (De Trin. ix): "By the fact of giving, the Father is greater; but He is not less to Whom the same being is given"; and (De Synod.): "The Son subjects Himself by His inborn piety"---that is, by His recognition of paternal authority; whereas "creatures are subject by their created weakness."

Reply to Objection 2: Equality is measured by greatness. In God greatness signifies the perfection of nature, as above explained (Article 1, ad 1), and belongs to the essence. Thus equality and likeness in God have reference to the essence; nor can there be inequality or dissimilitude arising from the distinction of the relations. Wherefore Augustine says (Contra Maxim. iii, 13), "The question of origin is, Who is from whom? but the question of equality is, Of what kind, or how great, is he?" Therefore, paternity is the Father's dignity, as also the Father's essence: since dignity is something absolute, and pertains to the essence. As, therefore, the same essence, which in the Father is paternity, in the Son is filiation, so the same dignity which, in the Father is paternity, in the Son is filiation. It is thus true to say that the Son possesses whatever dignity the Father has; but we cannot argue---"the Father has paternity, therefore the Son has paternity," for there is a transition from substance to relation. For the Father and the Son have the same essence and dignity, which exist in the Father by the relation of giver, and in the Son by relation of receiver.

Reply to Objection 3: In God relation is not a universal whole, although it is predicated of each of the relations; because all the relations are one in essence and being, which is irreconcilable with the idea of universal, the parts of which are distinguished in being. Persons likewise is not a universal term in God as we have seen above (Question 30, Article 4). Wherefore all the relations together are not greater than only one; nor are all the persons something greater than only one; because the whole perfection of the divine nature exists in each person.

Articulus 4

Argumentum 1

Ad quartum sic proceditur. Videtur quod filius non sit aequalis patri in magnitudine.

Dicit enim ipse, Ioan. XIV, pater maior me est; et apostolus, I Cor. XV, ipse filius subiectus erit illi qui sibi subiecit omnia.

Argumentum 2

Praeterea, paternitas pertinet ad dignitatem patris. Sed paternitas non convenit filio. Ergo non quidquid dignitatis habet pater, habet filius.

Ergo non est aequalis patri in magnitudine.

Argumentum 3

Praeterea, ubicumque est totum et pars, plures partes sunt aliquid maius quam una tantum vel pauciores; sicut tres homines sunt aliquid maius quam duo vel unus. Sed in divinis videtur esse totum universale et pars, nam sub relatione vel notione plures notiones continentur. Cum igitur in patre sint tres notiones, in filio autem tantum duae, videtur quod filius non sit aequalis patri.

Sed Contra

Sed contra est quod dicitur Philip. II, non rapinam arbitratus est esse se aequalem deo.

Corpus

Respondeo dicendum quod necesse est dicere filium esse aequalem patri in magnitudine. Magnitudo enim dei non est aliud quam perfectio naturae ipsius. Hoc autem est de ratione paternitatis et filiationis, quod filius per generationem pertingat ad habendam perfectionem naturae quae est in patre, sicut et pater. Sed quia in hominibus generatio est transmutatio quaedam exeuntis de potentia in actum, non statim a principio homo filius est aequalis patri generanti; sed per debitum incrementum ad aequalitatem perducitur, nisi aliter eveniat propter defectum principii generationis.

Manifestum est autem ex dictis quod in divinis est proprie et vere paternitas et filiatio. Nec potest dici quod virtus dei patris fuerit defectiva in generando; neque quod dei filius successive et per transmutationem ad perfectionem pervenerit.

Unde necesse est dicere quod ab aeterno fuerit patri aequalis in magnitudine.

Unde et Hilarius dicit, in libro de synod., tolle corporum infirmitates, tolle conceptus initium, tolle dolores et omnem humanam necessitatem, omnis filius secundum naturalem nativitatem aequalitas patris est, quia est et similitudo naturae.

Ad 1

Ad primum ergo dicendum quod verba illa intelliguntur dicta de christo secundum humanam naturam, in qua minor est patre, et ei subiectus. Sed secundum naturam divinam, aequalis est patri.

Et hoc est quod Athanasius dicit; aequalis patri secundum divinitatem, minor patre secundum humanitatem.

Vel, secundum Hilarium, in IX libro de Trin., donantis auctoritate pater maior est, sed minor non est cui unum esse donatur.

Et in libro de synod. Dicit quod subiectio filii naturae pietas est, idest recognitio auctoritatis paternae, subiectio autem ceterorum, creationis infirmitas.

Ad 2

Ad secundum dicendum quod aequalitas attenditur secundum magnitudinem. Magnitudo autem in divinis significat perfectionem naturae, ut dictum est, et ad essentiam pertinet. Et ideo aequalitas in divinis, et similitudo, secundum essentialia attenditur, nec potest secundum distinctionem relationum inaequalitas vel dissimilitudo dici.

Unde Augustinus dicit, contra maximinum, originis quaestio est quid de quo sit; aequalitatis autem, qualis aut quantus sit.

Paternitas igitur est dignitas patris, sicut et essentia patris, nam dignitas absolutum est, et ad essentiam pertinet.

Sicut igitur eadem essentia quae in patre est paternitas, in filio est filiatio; ita eadem dignitas quae in patre est paternitas, in filio est filiatio. Vere ergo dicitur quod quidquid dignitatis habet pater, habet filius. Nec sequitur, paternitatem habet pater, ergo paternitatem habet filius.

Mutatur enim quid in ad aliquid, eadem enim est essentia et dignitas patris et filii, sed in patre est secundum relationem dantis, in filio secundum relationem accipientis.

Ad 3

Ad tertium dicendum quod relatio in divinis non est totum universale, quamvis de pluribus relationibus praedicetur, quia omnes relationes sunt unum secundum essentiam et esse, quod repugnat rationi universalis, cuius partes secundum esse distinguuntur. Et similiter persona, ut supra dictum est, non est universale in divinis. Unde neque omnes relationes sunt maius aliquid quam una tantum; nec omnes personae maius aliquid quam una tantum; quia tota perfectio divinae naturae est in qualibet personarum.