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381
Anno Domini

Ecumenical Council

Council of Constantinople I

May–July 381 Constantinople Convoked by: Emperor Theodosius I 150 bishops 7 canons
Ecumenical Council — Universally Recognised
7Canons
Section I

The Crisis that summoned Council of Constantinople I

The apologetic argument: Defined the full divinity of the Holy Spirit (Pneumatomachian heresy condemned). Met without papal legates — recognised as ecumenical only retrospectively, after papal confirmation. Canon 3 placed Constantinople second in honour after Rome — confirming Rome's primacy.
The Ecumenical Councils

The Seven Ecumenical Councils

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