Letter 120: Leo, the bishop, to his beloved brother Theodoret, the bishop. On the return of our brothers and fellow priests, whom the See of the blessed Peter sent to the holy council, we ascertained, beloved, the victory you and we together had won by assistance from on high over the blasphemy of Nestorius, as well as over the madness of Eutyches. Wherefor...

Pope Leo the GreatTheodoret, of Cyrus, on Perseverance in Faith|c. 455 AD|leo great
arianismchristologymonasticismpapal authoritytravel mobility
Barbarian peoples/invasions; Theological controversy; Church council

Leo, Bishop of Rome, to his beloved brother Theodoret, Bishop of Cyrrhus.

I. He congratulates Theodoret on their shared victory, and approves of honest inquiry that leads to good results

On the return of our brothers and fellow bishops, whom the See of the blessed Peter sent to the holy council, we learned, beloved, of the victory you and we together have won -- with heaven's help -- over the blasphemy of Nestorius and the madness of Eutyches. We therefore make our boast in the Lord, singing with the prophet: "Our help is in the name of the Lord, who made heaven and earth" (Psalm 124:8). He did not allow us to suffer any harm through our brothers but rather confirmed, by the irrevocable assent of the whole assembly, what He had already established through our ministry. This demonstrated that what was first formulated by the foremost See of Christendom and then received by the judgment of the entire Christian world had truly proceeded from God Himself -- so that in this, as in all things, the members might be at one with the Head.

Our cause for rejoicing is all the greater when we consider that the fiercer the enemy's assault upon Christ's servants, the more he afflicted only himself. And lest the assent of other Sees to the decisions of the one See that the Lord appointed to take precedence should seem like mere complaisance, or lest any other base suspicion creep in, certain parties were found who disputed our definitions before they were approved. This was, in the Lord's mysterious providence, turned to our advantage, for by their very opposition they ensured that the faith emerged more clearly tested and more firmly established.

II. He praises the Council of Chalcedon's doctrinal achievement

The definition of the faith set forth at Chalcedon is no innovation. It is the faith of Nicaea restated and confirmed; the faith of the Apostles, of the Prophets, and of the Fathers, vindicated against both the heresy that divides Christ and the heresy that dissolves His true humanity. That definition now stands as the permanent standard of the Church's confession, and whoever opposes it opposes not the opinion of any single bishop but the consensus of the universal Church gathered under the guidance of the Holy Spirit.

III. He encourages Theodoret to persevere

As for yourself, beloved brother, continue with confidence in the work you have so faithfully carried out. You have endured unjust suffering for the sake of the truth, and the Lord has vindicated you. Do not be discouraged by the hostility of those who resent the triumph of orthodoxy. The same Providence that sustained you through trial will continue to uphold you.

I urge you to promote unity and peace among all the bishops of the East, and to work tirelessly so that the faith, now firmly established, may take root in every heart. Where there is uncertainty, bring clarity. Where there is weakness, bring strength. And where there is opposition, meet it with patience and with the irrefutable force of the truth itself.

Let us give thanks together that the Church has been delivered from so great a danger, and let us pray that no future storm may shake what has been so firmly built.

Dated from Rome.

Modern English rendering for readability. See the 19th-century translation or original Latin/Greek for scholarly use.

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