Pope St. Leo on Roman Primacy & the Filioque

I will be referencing specific extracts from the letters and sermons of Pope St. Leo related to the Roman Supremacy and the Filioque. All emphasis will be mine.

The following comes from Sermon 3, delivered on September 29, 443 AD, as translated in Leo The Great: Sermons (Fathers of the Church Patristic Series), and published by The Catholic University of America Press Publication in 1996, pp. 19-24.

Every time that God in his mercy sees fit to bring back the day of his gifts, dearly beloved, there is just and reasonable cause for us to rejoice, provided that the origin of our having received the office be referred to the praise of its source. I realize that this observance, appropriate as it is for all priests, is especially incumbent upon me.

Instead, it is the approval of heavenly grace that engenders the prelate.

When I compare the impoverishment of my insufficiency with the greatness of the gift I have received, I too should cry out in those words of the prophet: "Lord, I have heard your word and was afraid; I have considered your works and trembled.”²⁰ What indeed could instill as much anxiety and fear as labor for the frail, elevation for the lowly, dignity for the undeserving? Yet we do not despair or give up, since we do not depend on ourselves but on the one "who works in us.”²¹ So we have chanted with one voice the psalm of David, dearly beloved, not for our own exaltation but for the glory of Christ the Lord. He it is also of whom it was said in prophetic manner: "You are a priest forever according to the order of Melchisedech,”²² that is to say, "not according to the order of Aaron,”²³ whose priesthood passed down through the descent of his offspring and was a temporary ministry that ceased with the law of the Old Testament, but "according to the order of Melchisedech,”²⁴ in whom the office of eternal High Priest was prefigured. Since there is no mention of the parents he came from, he must be understood as standing for the one "whose genealogy cannot be told.”²⁵

Finally, since the mystery of this divine Priesthood also extends to its implementation by men, it does not pass down through the course of generations. It is not what flesh and blood have created that is chosen. Rather, the privileges of paternity give way and the social positions of families are disregarded, as the Church accepts for her rulers those whom the Holy Spirit has prepared. Among the people of God's adoption, which is priestly and kingly when taken as a whole,²⁶ the prerogative of earthly lineage does not obtain the anointing.

2. Therefore, dearly beloved, though we be found weak and slothful in carrying out the duties of our office-even if we want to accomplish something devoutly and energetically, we are slowed down by the very frailty of our condition-still, we have the constant propitiation of the omnipotent and perpetual Priest. Being at once like unto us and equal with the Father, he lowered his divinity to the human state and lifted his humanity up to the divine.

We rightly and piously rejoice in his arrangement because, although he has delegated the care of his sheep to many shepherds, he himself has not relinquished custody of his beloved flock. From his eternal protection derives the reinforcement of apostolic help that we have received. This never stops working either, and the stability of the foundation on which the height of the entire Church has been built up does not show any signs of straining, no matter how large the weight of the temple pressing down upon it. For the sturdiness of that faith which was praised in the leader of the apostles endures. Just as what Peter believed in Christ remains, there likewise remains what Christ instituted in Peter.

When-as it was unfolded in the Gospel reading-the Lord had asked the disciples whom they believed him to be, since there were many different opinions, and when the blessed apostle Peter had answered, saying, "You are Christ, Son of the living God," the Lord said, "Blessed are you, Simon, son of Jonah, because flesh and blood have not revealed this to you, but my Father who is in heaven. And I say to you that you are Peter and upon this rock I will build my Church, and the gates of hell will not prevail against it. And I shall give you the keys to the kingdom of heaven. And whatever you bind on earth, it will be bound also in heaven, and whatever you loose on earth, it will be loosed also in heaven.”²⁷

3. This pattern of truth remains. Persevering in the fortitude he received, blessed Peter does not relinquish his government of the Church. He was ordained before the others so that, when he is called rock, declared foundation, installed as doorkeeper for the kingdom of heaven, appointed arbiter of binding and loosing (with his definitive judgments retaining force even in heaven), we might know through the very mysteries of these appellations what sort of fellowship he had with Christ. He now manages the things entrusted to him more completely and more effectively. He carries out every aspect of his duties and responsibilities in him and with him through whom he has been glorified.

So, if we do anything correctly or judge anything correctly, if we obtain anything at all from the mercy of God through daily supplications, it comes about as a result of his works and merits. In this see his power lives on and his authority reigns supreme. This, dearly beloved, is what that confession has obtained. Since it was inspired by God the Father in the apostle's heart, it has risen above all the uncertainties of human thinking and has received the strength of a rock that cannot be shaken by any pounding.

In the universal Church, Peter says every day, "You are Christ, Son of the living God.”²⁸ "Every tongue" that "confesses the Lord,”²⁹ has been imbued with the teaching of this utterance. This faith binds the devil and loosens the chains of his captives. It ushers the outcasts of this world into heaven, and the gates of hell cannot prevail against it. So great is the firmness with which it has been divinely fortified that no heretical depravity can ever corrupt it and no pagan faithlessness overcome it.

4. Under these conditions then, dearly beloved, the celebration of today's feast involves a submission that conforms to reason. Regard him as present in the lowliness of my person. Honor him. In him continues to reside the responsibility for all shepherds, along with the protection of those sheep entrusted to them. His dignity does not fade even in an unworthy heir. On that account, the presence of my venerable brothers and fellow priests-though I have longed for it indeed and thought it something to be honored-has all the more sacred and devout a character if they redirect the reverence of this service, at which they have seen fit to be present, to the one whom they know to be not only the ruler of this see but the primate of all bishops.

When we present our exhortations to your holy ears, consider that you are being addressed by the one in place of whom we exercise this function. It is with his affection that we admonish you. We preach to you nothing other than what he taught, imploring that you "gird the loins of your minds," that you lead "a pure and sober" life "in the fear" of God,³⁰ and that your mind not consent to its concupiscences while forgetting its own primacy [over the body]. Brief and fading are the joys of earthly pleasures which try to divert those who are called to eternity away from the path of life.

(2) Let your faithful and devout minds conceive a passionate desire for heavenly things and lift themselves up, with eagerness for the divine promises, to love of the incorruptible good and to hope for the true light. Be assured, dearly beloved, that the labor by which you resist vices and repel carnal desires is pleasing in the sight of God and precious. It will be of benefit before the mercy of God not only to yourselves but to me also. It is from the progress of the Lord's flock that the shepherd's guardianship receives glory. "For you are my crown," as the Apostle said, "and my joy,”³¹ if "your faith," which was preached "in the whole world,”³² from the beginning of the Gospel, "will have persevered in love and holiness.”³³

Though all the Churches throughout the entire world ought to blossom with every virtue, it is especially fitting that you should stand out among other peoples in the merits of loyalty. You have been firmly planted in the very citadel of the apostolic rock. Our Lord Jesus Christ redeemed you along with all the rest, but the blessed apostle Peter instructed you before all others. Through Christ our Lord.

20. Hb 3.2.

21. Cf. 1 Cor 12.6, Eph 3.20, and Phil 2.13.

22. Ps 109(110).4 and Heb 5.6.

23. Heb 7.11.

24. Heb 6.20 and 7.11.

25. Is 53.8.

26. Cf. 1 Pt 2.9.

27. Mt 16.16-19.

28. Mt 16.16.

29. Cf. Rom 14.11.

30. Cf. I Pt 1.13 and 3.2.

31. Cf. Phil 4.1 and I Thes 2.19-20.

32. Cf. Rom 1.8.

33. Cf. I Tim 2.15.

The next citations are taken from  Letter 14 (Leo the Great).

XII. In case of difference of opinion between the Vicar and the bishops, the bishop of Rome must be consulted. The subordination of authorities in the Church expounded.

But if in that which you believed necessary to be discussed and settled with the brethren, their opinion differs from your own wishes, let all be referred to us, with the minutes of your proceedings attested, that all ambiguities may be removed, and what is pleasing to God decided. For to this end we direct all our desires and pains, that what conduces to our harmonious unity and to the protection of discipline may be marred by no dissension and neglected by no slothfulness. Therefore, dearly beloved brother, you and those our brethren who are offended at your extravagant conduct (though the matter of complaint is not the same with all), we exhort and warn not to disturb by any wrangling what has been rightfully ordained and wisely settled. Let none seek what is his own, but what is another's, as the Apostle says: Let each one of you please his neighbour for his good unto edifying. For the cementing of our unity cannot be firm unless we be bound by the bond of love into an inseparable solidity: because as in one body we have many members, but all the members have not the same office; so we being many are one body in Christ, and all of us members one of another. The connection of the whole body makes all alike healthy, all alike beautiful: and this connection requires the unanimity indeed of the whole body, but it especially demands harmony among the priests. And though they have a common dignity, yet they have not uniform rank; inasmuch as even among the blessed Apostles, notwithstanding the similarity of their honourable estate, there was a certain distinction of power, and while the election of them all was equal, yet it was given to one to take the lead of the rest. From which model has arisen a distinction between bishops also, and by an important ordinance it has been provided that every one should not claim everything for himself: but that there should be in each province one whose opinion should have the priority among the brethren: and again that certain whose appointment is in the greater cities should undertake a fuller responsibility, through whom the care of the universal Church should converge towards Peter's ONE SEAT, and nothing anywhere should be separated from its Head. Let not him then who knows he has been set over certain others take it ill that some one has been set over him, but let him himself render the obedience which he demands of them: and as he does not wish to bear a heavy load of baggage, so let him not dare to place on another's shoulders a weight that is insupportable. For we are disciples of the humble and gentle Master who says: Learn of Me, for I am gentle and humble of heart, and you shall find rest for your souls. For My yoke is easy and My burden light Matthew 11:29-30. And how shall we experience this, unless this too comes to our remembrance which the same Lord says: He that is greater among you, shall be your servant. But he that exalts himself, shall be humbled: and he that humbles himself, shall be exalted. 

The final excerpt is from Letter 15.

II. (1) The Priscillianists' denial of the Trinity refuted.

And so under the first head is shown what unholy views they hold about the Divine Trinity: they affirm that the person of the Father, the Son, and the Holy Ghost is one and the same, as if the same God were named now Father, now Son, and now Holy Ghost: and as if He who begot were not one, He who was begotten, another, and He WHO PROCEEDED FROM BOTH, yet another; but an undivided unity must be understood, spoken of under three names, indeed, but not consisting of three persons. This species of blasphemy they borrowed from Sabellius, whose followers were rightly called Patripassians also: because if the Son is identical with the Father, the Son's cross is the Father's passion (patris-passio): and the Father took on Himself all that the Son took in the form of a slave, and in obedience to the Father. Which without doubt is contrary to the Catholic faith, which acknowledges the Trinity of the Godhead to be of one essence (ὁμοούσιον) in such a way that it believes the Father, the Son, and the Holy Ghost indivisible without confusion, eternal without time, equal without difference: because it is not the same person but the same essence which fills the Unity in Trinity.

Further Reading

Pope Leo & Petrine Primacy