Gregory of Nyssa
Hierotheos Vlachos, metropolitan of Nafpaktos, wrote that according to Eastern Orthodox tradition, Gregory of Nyssa composed the section about the Holy Spirit in the Second Ecumenical Council's Niceno-Constantinopolitan Creed of 381. Siecienski doubted that Gregory of Nyssa "would have accepted the "filioque" as it was later understood in the West, although he witnesses to the important truth (often ignored in the East) that there is an eternal, and not simply economic, relationship of the Spirit to the Son."