Can someone explain to me why this is considered 'heresy' amongst some Orthodox?
I came across this statement on Tik Tok but, as I'm new to Orthodox and the church I am exploring is Ecumenical, am I doing the right thing?
Sorry, I don't know if it's called a church or a parish. Still getting to grips with terminology, God bless, CC
The main opposition to ecumenical reconciliation comes from Old Calendarists who are schismatic and not a part of the canonical Eastern Orthodox Church.
We also have a few canonical bishops who have said terrible things about other Christians, for example, Metropolitan Seraphim of Piraeus.
Ecumenical dialogue has had some impressive accomplishments, such as the ecumenical agreements that faciliate intermarriage and pastoral care between Coptic Orthodox and Alexandrian Greek Orthodox Christians, a vital agreement considering the shrinking size of the Alexandrian Greek population, who among the 118 million or so Egyptians now number less than 100,000, by facilitating their marriage to Coptic Orthodox Christians, who are probably now around 15 million in number given the increased birthrate.
Likewise, the even more expansive 1991 agreement between the Antiochian Orthodox and Syriac Orthodox, who in Syria are both gravely endangered, was a fruit of such dialogue.
Also through ecumenical dialogue many relics stolen by Roman Catholics have been returned, most importantly, the bodies of the Three Holy Hierachs (St. Basil the Great, St. Gregory the Theologian and St. John Chrysostom) which are now in the Patriarchal Cathedral of St. George in Constantinople.* Also the head of St. Mark, stolen with the rest of his relics, by the Venetian Republic, was returned to the Christians of Egypt (I believe it is with the Copts in Cairo but whatever the arrangement, the Alexandrian Greeks did not complain about it to my knowledge), and likewise other relics have been returned as well. Alas we still do not have the relics of St. Nicholas, but the Romans do at least give Orthodox pilgrims access.
* I am very thankful these are in Orthodox hands, although I wish they had been placed in Thessaloniki in retrospect, given the increased Islamicization of Turkey under Erdogan, although for now at least they are safe.