I challenge any Orthodox again to show from the Acts of the Councils where it says the Creed may never again be more fully explained by adding words that further clarify its meaning. The Council of Ephesus, which I quoted, says the exact opposite of what you claim.
It is forbidden to draw up a NEW CREED, meaning a NEW FAITH. Not to more fully explain the NICENE CREED. Otherwise, the actions of Chalcedon, Constantinople III, etc. were heretical because they added to the creed to more fully explain it.
And neither the original creed nor the Constantinoplitan addition and the Church father you posted mention the filioque in any way shape or form. It does not exist until the Pope inserted it and hereticed himself and his seat.
All the Church Father's I posted mentioned the filioque. Go read the quotes again.
we will discover all these things also in the Spirit, through the Son. - St. Athanasius, 3rd Letter to Serapion of Thmuis, 1 (360 AD)
they know in fact that the Father is the only cause of the Son and the Spirit, the one by begetting and the other by ekporeusis (procession) - St. Maximus the Confessor, Letter to Marinus, PG 91, 136
The Spirit of the Word is like a love of the Father...and it naturally rests on the Son - St. Gregory Palamas, Chapters, 36, PG 150:1144D-1145A
St. Cyril of Alexandria says that "the Holy Spirit flows from the Father into the Son (en to Uiou)," (Thesaurus, XXXIV, PG 75, 577A). You used a bogus Latin translation. For it to be "and the Son" would be expressed in Greek "kai to Uiou".
[Latins] know in fact that the Father is the only cause of the Son and the Spirit, the one by begetting and the other by ekporeusis (procession) - St. Maximus the Confessor, Letter to Marinus, PG 91, 136 in which St. Maximus gives the benifit of the doubt to Latins and chastises their translation - if their Latin filioque words mean that the Holy Spirit proceeds from the Father through the Son that is fine. He hopes that is the case because if the Latins really mean that the Holy Spirit proceeds from the Father and the Son then it would be in error. In other words the Greek understanding of the Trinity is correct and the Latin understanding of the Trinity is only correct if the Latin translation is in synch with the Greek meaning.