This marks the last post on the important terms that are related to the Trinity. But also, these terms are important to know in our daily Christian lives as they help us to know more about God. As we understand these terms more, they can help us have a deeper appreciation for each Person of the Trinity. They help us know more about each Person, how they relate to us, and can be useful in relating to them.
Procession: (Gk. ekporeuomai, Jn 15:26; Lat. processio, “to emanate from another”) In Trinitarian theology, as the Son is eternally generated from the Father, so the Holy Spirit eternally comes forth (proceeds) from the Father—“and [in Western theology] the Son” (Lat. filioque). The procession of the Spirit (or in the West the double procession) has traditionally distinguished the eternal relations of the Spirit within the Godhead. See Filioque.
Psychological Model of Trinity: Articulated by Augustine, this perspective suggests that since the human being is created in the imago dei and since God is Trinity, then human nature (expressed in activity) will reflect a threefoldness, e.g. in mind, knowledge, love of self; etc. Until recently, the West has preferred emphasizing the personal unity of God in the three “subsistencies” of the Father, Son, and Holy Spirit. See Social Model of Trinity.
Sabellianism: A 3rd century form of Modalism popularized by Sabellius, the teaching denied three distinct persons of the Trinity and, some surmise, posited three successive modes of divine manifestation from the Father of the OT, to the Son of the Gospels, to the Holy Spirit of Acts and the present age; deemed heretical. See Modalism, Monarchianism.
Social Model of Trinity: Loosely attributed to the Cappadocians but also expressed by Augustine, the Social Model explains the Trinity in terms of human relationships: e.g., Adam, Eve, and Seth (Basil); Lover, Beloved, Love itself (Augustine). Eastern Orthodoxy prioritizes the three persons (hypostases) over singularity of substance, affirms that each person shares the same attributes, locates divine unity in perichoresis, and often attributes ontological priority to the Father as the eternal source (fons totius divinitatis) of the full eternal deity of the Son and the Spirit. See Cappadocians,Perichoresis, Psychological Model.
Subordinationism: A view that holds that the Son or the Holy Spirit are inferior to the Father in nature or are less than co-equal in glory, as such deemed heretical. The term might also be used, not in terms of essential inequality of nature or glory, rather in terms of Trinitarian function, either temporarily in the economies of salvation, or even regarding eternal roles the members of the Godhead, e.g., eternal subordination of the Son to the Father; this latter meaning has been common in the history of both Eastern and Western Christianity.
Substance: (Lat. substantia, “that which stands under”) The Latin term substantia and persona and the Greek terms ousia and hypostasis were deemed equivalent in Triinitarian discussion for the East and West by Pope Damasus (366-84). See Essence, Nature, Ousia, Person.
Theophany: A manifestation of God in audible or usually visible form, conceivably in “heaven” as well as on earth (e.g., Ex 3:2-6; Da 7:9-10; Rev 4:2ff); such appearances are contrasted with the Incarnation which secured permanent union between the eternal Son and a human nature. See Incarnation.
Transcendence: The superiority of God over and apart from his created world; God is uniquely “other” from all created existence. See Immanence.
Trisagion: The Greek term for “thrice holy,” i.e., the ascription to the One on the heavenly throne as “Holy, holy, holy” (Isa 6:3; Rev 4:8); also ancient liturgy as the response, “Holy God, holy mighty, holy immortal, have mercy on us.”
Tritheism: (Lat. “three gods”) Heterodox theology in various forms through Christian history that deny the consubstantiality of the Father, Son, and Holy Spirit; unity is sacrificed to affirm divine diversity; deemed heretical. See Consubstantial.
Unitarianism: Variously expressed since the 16th century, the belief that denies the Trinity and deity of Christ, while affirming a single personal God; deemed heretical. See Deism, Monarchianism.