Filioque
Filioque est additamentum Latinum ad Symbolum Nicaenum Constantinopolitanum de processione Sancti Spiritus, quod in verbis ab ipso concilio anno 381 constitutis deest. Nihilominus ecclesia occidentalis quinto saeculo eam doctrinam de Trinitate introduxit, ut Arianismum, que maxime in Hispania vigebat, repudiaret. Ex 13. saeculo in ecclesia catholica Romana etiam dogmatice sanctum est, ita ut hodie et Catholici pariter atque Protestantes Credo cum illo filioque insertum confitentur. Praeter primatum papae maxime haec res reconciliationi utriusque ecclesiae orthodoxae et catholicae fidei, obstat.

Textus 

Textus apud plurimas ecclesias occidentales receptus:
[…] et in Spiritum Sanctum, Dominum et vivificantem, qui ex Patre Filioque procedit […]

Qui vero locus in textu Graeco, quem ut dogma haberi sanctum est, non nisi sic legitur:

[…]καὶ εἰς τὸ Πνεῦμα τὸ Ἅγιον, τὸ κύριον, τὸ ζωοποιόν, τὸ ἐκ τοῦ Πατρὸς ἐκπορευόμενον […]
hoc est: […] et in Spiritum Sanctum, Dominum et vivificantem, qui ex Patre procedit […]

Bibliographia
Abraham, W. (2002). Canonical Division Between East and West. Cap. 3 in Canon and Criterion in Christian Theology. Oxford University Press.
Abraham, W. (2018). The Person of the Holy Spirit. Vol. 3 cap. 7 in Divine Agency and Divine Action. Oxford University Press.
Baber, H. (2008). Trinity, Filioque and Semantic Ascent. Sophia, 47(2), 149-160.
Effingham, Nikk (2018). The philosophy of filioque.  Religious Studies, 54(3), 297-312.
Gemeinhardt, P. (2002). Die Filioque-Kontroverse zwischen Ost- und Westkirche im Frühmittelalter (Arbeiten zur Kirchengeschichte; 82).
Heron, A. (1971). ‘Who proceedeth from the Father and the Son’: The problem of the Filioque. Scottish Journal of Theology, 24(2), 149-166.
North American Orthodox-Catholic Theological Consultation, (2004). The Filioque: a Church Dividing Issue? An agreed statement. Greek Orthodox Theological Review, 49(3/4), 359-392.
Rawlinson, Alfred E. J. (1957). The Filioque Clause. Scottish Journal of Theology, 10(2), 166-173.
Siecienski, E. (2010). The Latin West. Cap. 3 in The Filioque. Oxford University Press.
Smith, S. (2014). The Insertion of the Filioque into the Nicene Creed and a Letter of Isidore of Seville. Journal of Early Christian Studies, 22(2), 261-286.

Concilium Toletanum III
Formula Trinitaria

Religio Christiana