I've realised something in the a certain translation to Portuguese of St. Justinian's Hymn that disturbed me a bit, specifically the line "Who art one of the Holy Trinity".
In the Polish Orthodox Church, we use "Tu que és um da Trindade Santíssima", which is exactly what the English translation says. Greek and Slavonic don't seem to exactly, literally, say that IMO, but I'm pretty sure neither adress Christ as a "part" of the Holy Trinity, which the translation used by a particular jurisdiction in Brazil (or at least part of it) says precisely: "Tu que és parte da Trindade Santíssima". I got the e-mail address from a priest that might change this if he realises this is wrong, but I'd like to get your opinion first, since I'm a bit shy about talking to priests, specially about such an intrincate issue: doesn't the idea that the Holy Trinity has "parts" recall the error of partialism, which in turn denies the indivisibility of the Holy Trinity? In that case, should I tell the priest to review this particular word choice? How should I address him?