Today’s Catechism sections cover the relationship of the Holy Spirit to the Father and Son. An excerpt from St. Gregory of Nyssa’s letter, “On the Trinity to Eustathius” provides the supporting material.

The Father and the son revealed by the spirit

243 Before his Passover, Jesus announced the sending of "another Paraclete" (Advocate), the Holy Spirit. At work since creation, having previously "spoken through the prophets", the Spirit will now be with and in the disciples, to teach them and guide them "into all the truth".68 The Holy Spirit is thus revealed as another divine person with Jesus and the Father.

244 The eternal origin of the Holy Spirit is revealed in his mission in time. the Spirit is sent to the apostles and to the Church both by the Father in the name of the Son, and by the Son in person, once he had returned to the Father.69 The sending of the person of the Spirit after Jesus' glorification70 reveals in its fullness the mystery of the Holy Trinity.

245 The apostolic faith concerning the Spirit was confessed by the second ecumenical council at Constantinople (381): "We believe in the Holy Spirit, the Lord and giver of life, who proceeds from the Father."71 By this confession, the Church recognizes the Father as "the source and origin of the whole divinity".72 But the eternal origin of the Spirit is not unconnected with the Son's origin: "The Holy Spirit, the third person of the Trinity, is God, one and equal with the Father and the Son, of the same substance and also of the same nature. . . Yet he is not called the Spirit of the Father alone,. . . but the Spirit of both the Father and the Son."73 The Creed of the Church from the Council of Constantinople confesses: "With the Father and the Son, he is worshipped and glorified."74

246 The Latin tradition of the Creed confesses that the Spirit "proceeds from the Father and the Son (filioque)". the Council of Florence in 1438 explains: "The Holy Spirit is eternally from Father and Son; He has his nature and subsistence at once (simul) from the Father and the Son. He proceeds eternally from both as from one principle and through one spiration... And, since the Father has through generation given to the only-begotten Son everything that belongs to the Father, except being Father, the Son has also eternally from the Father, from whom he is eternally born, that the Holy Spirit proceeds from the Son."75

247 The affirmation of the filioque does not appear in the Creed confessed in 381 at Constantinople. But Pope St. Leo I, following an ancient Latin and Alexandrian tradition, had already confessed it dogmatically in 447,76 even before Rome, in 451 at the Council of Chalcedon, came to recognize and receive the Symbol of 381. the use of this formula in the Creed was gradually admitted into the Latin liturgy (between the eighth and eleventh centuries). the introduction of the filioque into the Niceno-Constantinopolitan Creed by the Latin liturgy constitutes moreover, even today, a point of disagreement with the Orthodox Churches.

248 At the outset the Eastern tradition expresses the Father's character as first origin of the Spirit. By confessing the Spirit as he "who proceeds from the Father", it affirms that he comes from the Father through the Son.77 The Western tradition expresses first the consubstantial communion between Father and Son, by saying that the Spirit proceeds from the Father and the Son (filioque). It says this, "legitimately and with good reason",78 for the eternal order of the divine persons in their consubstantial communion implies that the Father, as "the principle without principle",79 is the first origin of the Spirit, but also that as Father of the only Son, he is, with the Son, the single principle from which the Holy Spirit proceeds.80 This legitimate complementarity, provided it does not become rigid, does not affect the identity of faith in the reality of the same mystery confessed.

IN BRIEF

263 The mission of the Holy Spirit, sent by the Father in the name of the Son (⇒ Jn 14:26) and by the Son "from the Father" (⇒ Jn 15:26), reveals that, with them, the Spirit is one and the same God. "With the Father and the Son he is worshipped and glorified" (Nicene Creed).

264 "The Holy Spirit proceeds from the Father as the first principle and, by the eternal gift of this to the Son, from the communion of both the Father and the Son" (St. Augustine, De Trin. 15, 26, 47: PL 42, 1095).

St. Gregory of Nyssa explains the unity of the Holy Spirit with the Father and Son in his letter, “On the Holy Trinity to Eustathius” in this way:

What, then, is our doctrine? The Lord, in delivering the saving Faith to those who become disciples of the word, joins with the Father and the Son the Holy Spirit also; and we affirm that the union of that which has once been joined is continual; for it is not joined in one thing, and separated in others. But the power of the Spirit, being included with the Father and the Son in the life-giving power, by which our nature is transferred from the corruptible life to immortality, and in many other cases also, as in the conception of Good, and Holy, and Eternal, Wise, Righteous, Chief,Mighty, and in fact everywhere, has an inseparable association with them in all the attributes ascribed in a sense of special excellence. And so we consider that it is right to think that that which is joined to the Father and the Son in such sublime and exalted conceptions is not separated from them in any. For we do not know of any differences by way of superiority and inferiority in attributes which express our conceptions of the Divine nature, so that we should suppose it an act of piety (while allowing to the Spirit community in the inferior attributes) to judge Him unworthy of those more exalted. For all the Divine attributes, whether named or conceived, are of like rank one with another, in that they are not distinguishable in respect of the signification of their subject. For the appellation of the Good does not lead our minds to one subject, and that of the Wise, or the Mighty, or the Righteous to another, but the thing to which all the attributes point is one; and, if you speak of God, you signify the same Whom you understood by the other attributes. If then all the attributes ascribed to the Divine nature are of equal force as regards their designation of the subject, leading our minds to the same subject in various aspects, what reason is there that one, while allowing to the Spirit community with the Father and the Son in the other attributes, should exclude Him from the Godhead alone? It is absolutely necessary either to allow to Him community in this also, or not to admit His community in the others. For if He is worthy in the case of those attributes, He is surely not less worthy in this. But if He is less, according to their phrase, so that He is excluded from community with the Father and the Son in the attribute of Godhead, neither is He worthy to share in any other of the attributes which belong to God. For the attributes, when rightly understood and mutually compared by that notion which we contemplate in each case, will be found to imply nothing less than the appellation of God.

Footnotes

68 Cf. ⇒ Gen 1:2; Nicene Creed (DS 150); ⇒ Jn 14:17, ⇒ 26; ⇒ 16:13.
69 Cf. ⇒ Jn 14:26; ⇒ 15:26; ⇒ 16:14.
70 Cf. ⇒ Jn 7:39.
71 Nicene Creed; cf. DS 150.
72 Council of Toledo VI (638): DS 490.
73 Council of Toledo XI (675): DS 527.
74 Nicene Creed; cf. DS 150.
75 Council of Florence (1439): DS 1300-1301.
76 Cf. Leo I, Quam laudabiliter (447): DS 284.
77 ⇒ Jn 15:26; cf. AG 2.
78 Council of Florence (1439): DS 1302.
79 Council of Florence (1442): DS 1331.
80 Cf. Council of Lyons II(1274): DS 850.