Letter LIV is addressed to Emperor Theodosius II on Christmas Day 449 — four months after the Latrocinium and with no resolution yet in sight. The letter is short, as Leo’s letters to Theodosius tend to be: the emperor had already received the full doctrinal exposition through the letters carried by Epiphanius (the cluster of October 13 letters and the Tome that preceded them), and Leo is not repeating himself. Instead he makes two crisp moves — the doctrinal equation and the practical request — and leaves them for Theodosius to act on.

The doctrinal move is the more fundamental. Leo states plainly that Eutyches is to be condemned no less than Nestorius — that both are anathematized by the same rule of Catholic faith. This was not merely a theological point; it was a direct rebuttal of the entire framing of Ephesus II. The council had presented itself as the defender of Cyril’s anti-Nestorian tradition against a Nestorian resurgence, with Theodoret, Flavian, and the others cast as crypto-Nestorians. Leo’s position demolishes this framing: the Nicene faith condemns both errors equally, and a council that vindicated Eutyches against Flavian was not defending Nicaea but departing from it.

The practical move is the Italian council request. After Ephesus II, Leo understood that an Eastern council held under Eastern conditions could be dominated by the Alexandrian party as Ephesus had been. An Italian council would be a different kind of institution — one where Leo could ensure proper procedure, where the Tome would be the doctrinal baseline, and where no single Eastern patriarch could control the proceedings the way Dioscorus had. The request was never granted in the form Leo asked: Theodosius refused to authorize an Italian synod. But the pressure Leo applied through this and his other correspondence to the emperor, the empress Pulcheria, and the ecclesiastical establishment ultimately contributed to the conditions that produced Chalcedon in 451 — held in the East but negotiated to prevent a repetition of the Latrocinium.

The Christmas dateline is worth pausing over. December 25 is the Feast of the Nativity — the birth of the Incarnate Word — not to be confused with the Feast of the Incarnation proper, which falls on March 25 (the Annunciation). But the Nativity is itself a celebration of the truth the letter is defending: that the eternal Son of God genuinely took flesh from the Virgin and was born into the human race. Whether the choice of December 25 was deliberate or simply the day Leo completed the letter, a letter demanding that the emperor act to preserve the doctrine of Christ’s true humanity, written on the day the Church commemorates the birth of that humanity, carries an resonance that the reader is unlikely to miss.