In another place we can find the statement that the Holy Spirit "proceeds from the Father and from the Son." This text is quoted primarily by those who want to see in St. Ambrose the defender of the Latin doctrine of the Filioque. But it is enough to place this passage in its context to see at once that the bishop of Milan puts this statement in the perspective of oikonomia: "The Holy Spirit is not sent out to depart from a place, nor is the Son Himself when He says, 'I came forth from God, and have come' (Jn. 8, 42) […]. The Son, neither when He proceeds from the Father, departs from there and is separated from Him, as the body is separated from another, nor when He is with the Father, is He continued by Him, as a body that is continued by another. His Holy Spirit, too, when He proceeds from the Father and from the Son (procedit a Patre et a Filio), is not separated from the Father, is not separated from the Son."74

St. Ambrose wants to show here clearly the unity of the nature of the three Divine Persons, or rather, he wants to make it clear that by virtue of this unity in the generations the three Persons are not separated from one another, when the Son proceeds from the Father to be sent into the world, or when the Holy Spirit proceeds or is sent from the Father and from the Son, being sent by the Son from the Father.75 Other passages also consider this unity of nature in perspective, which in the meantime may seem unquestionably theological, and not oikonomic. Thus, St. Ambrose writes:

"He who proceeds from another is either from His essence or from His power: from essence, like the Son who speaks. I have come (prodivi) out of the mouth of the Most High (Sir. 24:3), or as the Spirit Who proceeds (procedit) from the Father (John 15:26) and of whom the Son says: "He will glorify Me, because He will receive from Mine (John 16:14)." He also notes that the Son takes everything from the Father "through the unity of their nature (per unitatem naturae), and all that the Spirit receives from the Son receives through the same unity (per eamdem unitatem) as the Lord Jesus Christ Himself declares it of the Holy Spirit".77 And in another place he writes: "Is there anything more obvious than this unity? Everything that the Father has, the Son has, everything that the Son has, the Holy Spirit also receives THIS."78

[On the one hand, as confirmed by St. Ambrose, the Holy Spirit proceeds from the Father. On the other hand, all the texts speak frankly of the transmission from the Father to the Son and from the Son to the Spirit (or from the Father through the Son to the Spirit,80) of all good things, all the qualities or all the actions or energies of the divine nature.81 These goods, actions, or energies are distinct from nature (or substance or essence) as such, as St. Ambrose himself has clearly made clear elsewhere.82 Whereas that which was received by the Spirit from the Father through the Son (or also from the Son) was received by the Spirit from the One Father at the same time as His personal or hypostatic existence. Elsewhere in the text it can be seen that the unity of nature is in a sense preceded by the communication from one Person to another of the goods or energies that are united to this nature (the Son, says St. Ambrose, takes everything from the Father, and the Spirit takes everything from the Son through the unity of their nature). What is said here about the goods that belong to nature, and not about nature as such, is confirmed by the fact of which St. Ambrose says: "What the Father has is with the Son, what the Son has, the Spirit also receives it," and this is not what the Father is, nor what the Son is. Here we see the idea, widespread among the Fathers, that "the Spirit takes from the Son", and in connection with this the words of Christ: "He will receive from Mine" (John 16:14); an idea which the Fathers interpreted, like St. Hilary, as the communication of Divine goods (or energies or actions of the "Divine nature").

On the basis of these latter texts and their importance, St. Ambrose appears to be one of those Latin Fathers to whom St. Maximus appeals in order to confirm the use of the expression "The Spirit proceeds also from the Son" to signify that the Father and the Son have one and the same nature (St. Ambrose has in mind, like St. Hilary, to defend the divinity of Christ, denied by the Arians). The theology of St. Ambrose is correlated in another place with the criterion of orthodoxy given by St. Maximus: it is obvious that St. Ambrose does not see in the Son the Cause or the Beginning of the Spirit, and as far as His personal existence is concerned; The Holy Spirit proceeds from the Father alone, as is shown by numerous passages in his writings.83 Thus Ambrose writes: "The Spirit proceeds at the same time from the Father and bears witness to the Son (a Patre procedit Spiritus Sanctus et testificatur de Filio)." He also observes: "His procession takes place without mediation and goes back to the One who never began, because the Father had no beginning, and since He had no beginning, the Spirit also did not have one, for the reason that He is in Him and He is His".85 In addition, one can quote a remark that openly indicates that St. Ambrose does not at all interpret the biblical expression "Spirit of the Son" in the sense of the procession of the Holy Spirit, who has the Son as His Beginning: "If you say 'Spirit,' you are at the same time naming God the Father, from whom the Spirit proceeds, and the Son, because the Spirit is also the Son."86 St. Ambrose himself reveals the difference between expressions that refer to the origin of the existence of the Holy Spirit and those that emphasize the unity of nature.

For example, he notes: "The Holy Spirit proceeds from the Father, and He possesses, together with the Father and the Son, the same deity, the same action, and the same essence (procedentem ex Patre, et communem Patre et Filio deitatem, operationem et substantiam possidentem)."

The same difference is seen in the words of Christ Himself, when He says: "The Spirit of truth, who proceeds from the Father, and at the same time the Spirit is sent through the Son because of the community and unity of nature (propter societatem unitatemque naturae a Filio mittitur)," and the open manifestation of the unity of nature is here placed in a distinctly house-building perspective, because it is openly connected with mission. It will be possible to note the closeness of these last words of St. Ambrose to the words of St. Maximus: "They wanted to discover the work (of the Holy Spirit) to proceed (through the Son) and thereby establish the affinity and indistinguishability of the essence," as St. Ambrose, one of the Latin Fathers, whom St. Maximus had in mind in his letter, asserts in a different way than St. Ambrose, one of the Latin Fathers, whom St. Maximus had in mind in his letter.

St. Leo the Great

The only place where one can find a direct and intelligible judgment about the procession of the Holy Spirit in the writings of Pope St. Leo the Great is in his "Epistle 15" from Turribius d'Astroga, where he, in particular, writes about the Holy Spirit: "de utroque processit" [from both he came – Ed.] 89. But today it is known that this piece is apocryphal and was fabricated after the Council of Braga (563) 90.

The assertion that the Holy Spirit is "the common Father and the Son,"91 or that He is the Spirit of the Father and the Spirit of the Son,92 which was a common belief among the Fathers, echoing the expressions of the Holy Apostle Paul, "the Spirit of the Father" and "the Spirit of the Son," do not affect the origin of the Spirit.

One of the texts where this last statement can be found clarifies the concept of St. Leo and presents an analysis that sheds light on the subject with which we are interested. Speaking of Pentecost, the Pope notes:

"Let us beware of thinking that the Divine substance was manifested in that which was pointed out to the eyes of the flesh. The divine nature, invisible and common to the Father and the Son, has indeed shown under the sign under which it willed the quality of its gift and its work (muneris atque opens sui), but it has retained in the depths of its divinity that which is proper to its essence: for the gaze of man, not only cannot reach the Father or the Son, he cannot even see the Holy Spirit. In the Divine Trinity there is, indeed, nothing dissimilar, nothing unequal; Everything that can be imagined of this substance does not differ in power, glory, or eternity (dog virtute, dog gloria, dog aeternitate). Although according to the properties of the Persons there is one Father, another is the Son, another is the Holy Spirit, nevertheless neither Divinity becomes different, nor nature is different. If indeed the Only-begotten Son is of the Father, and the Holy Spirit is the Spirit of the Father and the Son, He is not like a creature which would be the Father and the Son, but He is as having life and power with the One and with the Other, and as eternally existing from what the Father and the Son are (sempiterne ex eo quod est Pater Filiusque subsistens). Likewise, when the Lord, on the eve of His Passion, promised His disciples the sending of the Holy Spirit, He said to them: "When He, the Spirit of truth, comes, He will guide you into all truth: for He will not speak of Himself, but will speak what He hears, and will declare things to come. […] All that the Father has is Mine; therefore I have said that He will take of Mine and declare it unto you (John 16:13,15). Thus, it would be wrong to assert that some things belong to the Father, some to the Son, and some to the Holy Spirit. No, that which belongs to the Father belongs to the Son and to the Holy Spirit. Never in this Trinity can such a community have a flaw, for, possessing everything, She exists eternally (semper existere). Let us beware of imagining any time, any degree, any difference; and if no one can explain what God is, let no one dare to assert that He is not. It is more excusable, in fact, not to speak with dignity of ineffable nature than to define it by what is contrary to it. Likewise, all that zealous hearts can imagine of the eternal and immutable glory of the Father, they at the same time inseparably and indistinguishably conclude about the glory of the Son and the Spirit. In fact, we confess that this blessed Trinity is One God, because in these three Persons there is no distinction of substance, power, will, or action (dog substantiae, dog potentiae, dog voluntatis, dog operations est ulla diversitas).93