This Going Forth of the Spirit is conceptualized after the manner of the going forth of breath from the mouth, and hence it is wont to be called Spiration relative to Him, from whom He goes forth. Whither leads, 1. the Name Spirit, which is everywhere wont to be given to the third person in contradistinction to the Father and the Son, and so not with respect to the Spirituality of the divine nature, which is common to the three Persons; neither uniquely nor primarily with respect to His operations in those elect and believing: but, as the Names of Father and Son are sought from the characteristic and person property of these Persons, so the Name of Spirit also leads us to the Mode of subsistence in the divine Nature, peculiar to this Person, whereby, after the likeness of the breath of the mouth, He is Spirated and goies forth from God, which manner of subsistence is also followed by the manner of operation. 2. This Spiration is further founded on the description of this Spirit as the Spirit of the mouth of the Lord, Psalm 33:6; indeed, as the breath of the Almighty, Job 33:4: see SCHULTENS. 3. To which the Symbol in John 20 :22 is also able to have regard, to indicate that Spirit, who after the likeness of breath proceeds from the mouth of God, in a manner similar to the likeness of the powerful afflatus that was about to affect the Apostles also : compare LAMPE, Dissertationum philologico-theologicarum, volume II, chapter VI, de Spiritu Sancto, § 1-6, Disputation VI, pages 194-198.
This Spiration and Procession of the Spirit, eternal and natural, no less than the divine Generation and Nativity of the Son, orthodox Theologians expound of the Communication of the Numerically Same Divine Essence made to the Holy Spirit. BEZA, in his Quæstionum et Responsionum Christianarum libello, Tractationum Theologicarum, volume I, page 670: “Those individual Persaons are one and the same perfect God, coeternal, coessential, coequal, although in order (not degree) the Father is first, who is from none: the Son is second, who is from the Father: the Holy Spirit is third, who is from the Father and the Son, each indescribably by the eternal Communication of the whole Essence of God, the former indeed begotten, but the latter emanating.” URSINUS, Explicationum Catecheticarum, on question XXV, pages 179, 180: “The Father is the first person…He communicates Deity to the Son and the Spirit…. The Holy Spirit is the third person: because deity is communicated to Him by the Father and the Son through eternal Spiration…. Now, although this is to be acknowledged, the manner of eternal…Procession…is ἄῤῥητον/ ineffable by us men…nevertheless, with certainty we gather the matter itself from Scripture: …that Procession or emanation is the Communication of the divine Essence, whereby only the third person receives the same and entire Essence of divinity, which the Father and the Son have and retain, from the Father and the Son, as the Spirit from Him, whose Spirit He is.” POLANUS, Syntagmate Theologiæ, book III, chapter VI, pages 218, 219: “The Holy Spirit’s Mode of subsistence is, that He comes forth from the Father and the Son by eternal and equal Procession or Spiration, with that whole Essence of Deity communicated to Him by that, in which Essence they also subsist…. The Holy Spirit’s Procession or emanation is the mode of the Communcation of the divine Essence, whereby the third person receives the same and whole Essence of the Deity from the Father and the Son, as the Spirit from Him, whose Spirit He is, while the Father and Spirit have and retain the same and whole Essence. For the whole divine Essence is given by the Father and the Son to the Holy Spirit, not by alienation, nor multiplication, of the Essence, but by communication of the numerically same Essence, in which they also subsist, in such a way that the Essence of Deity is common to the three persons. To be communicated and to proceed are not the same thing. For, that which is communicated does not proceed, but He proceeds, to whom the substance of the one spirating is communicated. The divine Essence is communicated; it does not proceed:” so also THYSIUS in Synopsi purioris Theologiæ, Disputation IX, § 8. GOMARUS, Disputationum Theologicarum VIII, § 12: “The Holy Spirit is the third person of the Deity, who through eternal, internal, and natural, second and final, Communication of the divine Essence, proceeds from the Father and the Son in an incomprehensible Spiration:” which he then expounds at greater length in his opera, part III, pages 28-30. CLOPPENBURG, Exercitationibus Theologicis, locus III, Disputation II, section I, § 8: “…Which the priority argues, wherewith the Son in the Trinity is a Person prior to the Person of the Holy Spirit. Which priority is through the first Communication of Essence, whereby the Father and the Son are one first, John 10:30, 38. But the second Communication of Essence is that from the Father and the Son, whereby the three are one, 1 John 5:7.” Likewise in section II, § 15: “The Third Person of the Deity is the Holy Spirit, proceeding from the first and second persons, as from the origin of subsistence, not the cause of the Essence, through the eternal and natural, second and final, communication of the Essence, whereby those three are one, and third abiding in the first and second, coeternal and coequal.” HEINRICH ALTING, Locis Communibus, part I, locus III, Scriptorum Heidelbergensium, tome I, page 42: “But, what this Procession might be, and how it might differ from the Generation of the Son, has not been much explained in the Word of God. It is evident in general…that there has been a Communication of the divine Essence from the Father and the Son. For, as the Father has given subsisting life to the Son, John 5:26, so also the Father and the Son to the Holy Spirit…by Communication, so that it is common to the three Persons of the Deity.” FREDERIC SPANHEIM, Disputationum Theologicarum, part I, Disputatione de Trinitate, § 16, page 50: “The Mode whereby the Holy Spirit is from the Father and the Son is described by Ἐκπόρευσιν or by Procession…. It is certain that that Procession…is an indivisible Communication of the same Essence. It is able to be described, that it is the mode of Communication of the divine Essence, whereby the third Person of the Trinity has from the Father and the Son the same Essence as both the Father and the Son have.” TURRETIN, Theologiæ Elencticæ, locus III, question XXXI, § 2: “The question does not concern the temporal and external Procession, etc.: But the eternal and internalProcession, which is terminated ad intra, and is nothing other than the mode of the Communication of the divine Essence, whereby the third Person of the Trinity has the numerically same Essence from the Father and the Son, as the Father and the Son have.” REINERUS VOGELSANG, Exercitationibus theologicis XIII, § 13: “In the divine it is of no lesser perfection to be brought forth and to have Deity communicated that to bring forth and to communicate Deity. But either the Father alone communicates to the Son, or the Father together with the Son communicates to the Holy Spirit, not only one and the same Essence, but also the whole Essence: and that with the most absolute necessity.” In § 14: “Now, we acknowledge a twofold mode of the Communication of the divine Essence, and so a twofold bringing forth among the divine Persons, namely, Generation and Spiration.” In § 20: “Therefore, we judge that that Spiration is not incommodiously described as an internal act and tending inwardly, common to the Father and the Son, whereby God, turned back upon Himself, by the Communication of the same Essence, differentiates the third and final Person. To this corresponds Procession, more particularly expressed.” Making use of the same manner of speaking above, § 8, we heard the Theologians of Leiden, SPANHEIM the Younger, TRIGLAND the Younger, and MARCKIUS, in their Judgment concerning the opinion of Röellius on the Generation of the Son. But also their Successors, with the same MARCKIUS, FABRICIUS, WESSELIUS, and TACO HAJO VAN DEN HONERT, in their Judicio Ecclesiastico contra Röellium laudato, chapter III, § 14, page 107, with confidence assert: “The Procession of the Holy Spirit, delivered in the Scriptures, asserts, according to the Catholic Faith, the Eternal and altogether Supernatural Communication of the Same Divine Essence; of which Communication there is sufficiently evident to us no Difference from that which obtains in the Generation of the Son, except that the Scripture makes use of different words in expressing the one and the other Communication, and that the Spirit does not communicate the same Essence in addition, as the Son does.” STAPFER, Theologicæ polemicæ, tome 3, chapter XII, § 233: “The Father gave to the Son all the reality of divinity, with the Property of Paternity excepted; both the Father and the Son communicated with the Holy Spirit the whole divine Nature, with that active Spiration excepted, whereby the third Person differs from the first and the second.” Among the Lutheran Theologians JOHN GERHARD, Locis Communis, tome I, de Spiritu Sancto, chapter III, § 43, page 153: “He that proceeds eternally from the Father and the Son is true God. The Holy Spirit proceeds eternally from the Father and the Son. Therefore, He is true God. The Major is confirmed from this, that that Procession is nothing other than the Communication of the divine Essence through eternal Spiration from the Father and the Son.” BUDDEUS, Theologiæ Dogmaticæ, tome I, book II, chapter I, § 52, page 392: “Generation and Spiration are personal Acts…. The very rationale of those consists in the Communication of the divine Essence. Whence it is evident at the same time, that only two personal Acts of this sort are able to be, Generation and Spiration, taken actively, since there are only two Persons, with whom the Essence is communicated, the Son and the Holy Spirit. Those Acts agree in this, that both denote a certain Communication of the divine Essence, and both are eternal.”
 Psalm 33:6: “By the word of the Lord (בִּדְבַ֣ר יְ֭הוָה) were the heavens made; and all the host of them by the breath of his mouth (וּבְר֥וּחַ פִּ֜֗יו, by the Spirit of His mouth).”  Job 33:4: “The Spirit of God (רוּחַ־אֵל) hath made me, and the breath of the Almighty (וְנִשְׁמַ֖ת שַׁדַּ֣י) hath given me life.”  Franciscus Fabricius (1663-1738) was a Dutch Reformed Theologian; he served as Professor of Theology at Leiden (1705-1738).