I pulled this Greek from a source on the internet so someone can please check if it really does come from the 7th oecumenical council.
το εκ του πατρος δια του υιου εκπορευομενον
The TO is a relative pronoun whose substantive is
TO turns into QUI in Latin.
EK turns into EX in Latin
TOU could have been translated but as the definite article in Latin is more often used as a third person pronoun we don’t translate this.
PATROS is of course in the genitive and is governed by EK.
In Latin we use PATRE, which is an ablative, and is governed by EX.
Then DIA means through and would be translated as PER in Latin but the Ablative if Means works just as well.
This relative clause it interesting in that I have seen the creed in Greek where the verb was not at the end but it is here. This is important in a relative clause.
Also, I noticed that the word KAI was not between EK TOU PATROS and DIA TOU UIOU.
In Latin since this is a relative clause -que is what lets us know that Filio is not governed by the preposition that governs Patre. We kind of need it unless we put Filio before EX PATROS.
If I were doing the translation I would put it as
Qui Filio ex Patre procedit.
Then I would just hope that people didn’t try to say that I was giving more honor to the Son by mentioning him first.
Qui ex Patre per Filium procedit
works just as well if we explain that we are forcing the “by means” construction regardless of the verb of motion. Most modern people should have no problem with this, only the Latin Grammaterians.
Does anyone else have a better source?