Scott Swain’s new book, The Trinity: An Introduction, is now available from Crossway—an entry in the relatively new series Short Studies in Systematic Theology, edited by Oren Martin and Graham Cole.
The following is adapted from his glossary. These can sound a bit technical, but they are worth reading and rereading and absorbing to learn the language and grammar of classical Trinitarian theology. Seriously—read these over and over again until the categories are fixed in your mind.
Kevin Vanhoozer writes: “This is a wonderful primer to the grammar of ‘Trinitarian discourse,’ a grammar that is needed not simply to talk theological shop with the professionals but, more importantly, to read the Bible fluently, to name God correctly, to discern the true triune God from idols, and to praise the name of the one who invites us into the fellowship of the Father and the Son through the Spirit.”
person. In Trinitarian theology, this term identifies that which distinguishes the Father, the Son, and the Spirit from each other.
Though the term has various secular uses in the ancient and modern worlds, its use in Trinitarian theology likely originates in the practice of prosopological exegesis.
(Prosopological exegesis is an ancient reading strategy commonly employed by Greco-Roman readers, New Testament authors, and the church fathers. This strategy involves clarifying the otherwise ambiguous identity of speech agents in conversations recorded in a sacred text. Prosopological exegesis addresses questions such as Who is speaking in this text? and To whom is the speaker speaking in this text?)
According to Boethius’s influential definition, a person is “an individual substance of a rational nature.” In other words, a person is not merely an individual something; a person is a certain kind of individual, an individual someone, characterized by and worthy of knowledge and love.
Because that which individuates the persons of the Trinity is each person’s relation of origin, Thomas Aquinas defines a Trinitarian person as a “subsisting relation.”
relation(s) of origin. That (and that alone) which distinguishes one person of the Trinity from other persons of the Trinity is the manner in which he is eternally related to another person of the Trinity as his personal principle or source.
- The Father has no eternal personal principle or source.
- The Father is the eternal personal principle or source of the Son through begetting the Son.
- The Father and the Son are the eternal personal principle or source of the Holy Spirit through breathing the Holy Spirit.
personal property. The unique identifying feature of each person of the Trinity that distinguishes him from the other two.
- The Father’s personal property is paternity.
- The Son’s personal property is filiation.
- The Spirit’s personal property is passive spiration.
paternity. The personal property of the Father that identifies him as the divine person who eternally begets the person of the Son. While the Father eternally begets the Son (and, with the Son, eternally breathes out the Spirit), the Father himself has no relation of origin.
filiation. The personal property of the Son that identifies him as the divine person eternally begotten by the person of the Father. Filiation names the Son’s distinctive personal relation of origin.
passive spiration. The personal property of the Holy Spirit that identifies him as the divine person eternally breathed out by the person of the Father and the person of the Son. Passive spiration names the Spirit’s distinctive personal relation of origin
(active spiration. Though not a personal property in the strict sense of the term, because it is held in common by the person of the Father and the person of the Son, active spiration identifies the Father and the Son as the persons who eternally breathe out the person of the Holy Spirit.)
mission. In Trinitarian theology, this term refers to one divine person “sending” another divine person in time to accomplish God’s undivided work of salvation:
- The Father sends the Son to become our incarnate Redeemer and Lord.
- The Father and the Son send the Spirit to indwell, enliven, and sanctify us.
In the missions of the Trinity, the eternal relations of origin are extended to creatures in time:
- The Father who eternally begets the Son sends his Son to us in order that we might receive the gift of adoption.
- The Father and the Son who eternally breathe out the Holy Spirit send the Holy Spirit to us in order that we might be sanctified for fellowship with the triune God.