How is it that Nestorius is venerated in the Syro-Malabar Catholic Church?
Even though Syro-Malabarian Catholics do not actually venerate Nestorius as other Saints but there is a (pseudepigraphal) Anaphora is attributed to Him, and as such hold him in high esteem. Wikipedia is not always the best source to go to, especially when historical evidence and documentation is lacking.
There are several Anaphora in the Eastern Churches.
Oriental Churches use three Anaphoras , that of Addai et Mari, of Theodore and Nestorius (attributed to Nestorius). In the Greek Rite the Anaphoras are numerous while in the Roman Rite the Canon of the Mass is from time immemorial quite invariable.
This said the Syro-Malabar Catholic Church still honours him as having influenced their Estern Rite, by employing the Anaphora of Nestorius on occasion. This does not in itself imply sainthood.
It seems that Nestorius was in fact never formally excommunicated by the pope. Nor is he recognized as a saint in any Catholic Liturgical Rite, East or West. Why Wikipedia employed the term veneration in regards to Nestorius and the Syro-Malabar Catholic Church is not clear to me.
Despite many anathematizes, Nestorius was never officially excommunicated by the Church. Numerous bishops pronounced such against him. The pope even condemned his doctrines, but never officially excommunicated (anathema) him.
Much has been lost to history so we may never truly understand the full accounts of these heresies of Nestorianism and how or if they are actually (fully) upheld by Nestorius himself.
Cyril had to explain that he was not summarizing or defining the faith about the Incarnation, but simply putting together the principal errors of Nestorius in the heretic's own words. In his books against Nestorius he had occasionally misrepresented him, but in the twelve anathematisms he gave a perfectly faithful picture of Nestorius's view, for in fact Nestorius did not disown the propositions, nor did Andrew of Samosata or Theodoret refuse to patronize any of them. The anathematisms were certainly in a general way approved by the Council of Ephesus, but they have never been formally adopted by the Church. - Nestorius and Nestorianism
The Council of Ephesus was a council of bishops convened in Ephesus in 431 AD by the Emperor Theodosius II. This third ecumenical council, an effort to attain consensus in the church through an assembly representing all of Christendom, confirmed the original Nicene Creed, and condemned the teachings of Nestorius, Patriarch of Constantinople, who held that the Virgin Mary may be called the Christotokos, "Christ-bearer" but not the Theotokos, "God-bearer". It met in June and July 431 at the Church of Mary in Ephesus in Anatolia.
Pope Celestine had died on July 26 and the Council of Ephesus ended on July 31 and thus he could not have confirmed the decisions of the council.
Nowadays only the Pope can excommunicate a bishop outside automatic excommunications as stated in Canon Law. Back then I guess the rules were not so clear.
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