God’s triunity: the central mystery of the Christian faith
“The mystery of the Most Holy Trinity is the central mystery of Christian faith and life. It is the mystery of God in himself. It is therefore the source of all the other mysteries of faith, the light that enlightens them” (¶234)1. God’s oneness and threeness are both equally basic to the being of God.
The oneness of God goes back to the origins of Israel and the Jewish faith. The most famous verse in the Old Testament is called the Shema, and it begins with, “Hear, O Israel: The LORD our God is one LORD …” God is one because God is utterly unique; divinity belongs solely and exclusively to him. God’s threeness is revealed by Jesus Christ who both affirms that God is one and identifies himself with this one God by identifying himself as the LORD (¶202). When Jesus ascended to be with the Father, he sent the Holy Spirit at Pentecost as the Giver of Life, the Comforter, and the Counselor. The Spirit’s descent at Pentecost revealed that God is not simply two persons but rather three persons. God is not binitarian but rather trinitarian: God is triune. God is thus one-in-three and three-in-one. Oneness and threeness are both equally basic to the being of God. We must understand the oneness of God in light of his threeness, and we must understand the threeness of God in light of his oneness. The triunity of God is a deep mystery which human reason cannot penetrate (cf. ¶206, 237), but it is a mystery which God reveals to us by grace and with which God brings us into perfect union and communion (¶259-60).
2. We must distinguish between the immanent and economic Trinity.
In ¶236 the Catechism discusses the distinction between “theology” and “economy.” Theology here means the study of who God is in and for himself, whereas the economy refers to what God does in time and space. In church theology, we use the terms “immanent Trinity” and “economic Trinity” to say the same thing. The former refers to God’s inner triune life, while the latter refers to God’s external triune life. Some theologians think we can only speak about God’s economy, but this means revelation is not really revelation of God. According to the Catechism, the immanent Trinity is revealed by the economic Trinity, while conversely the immanent Trinity “illuminates” the economic Trinity. We know who God truly is in himself through what God does for us in time. As a result, the incarnate Son reveals the Father, and the Holy Spirit reveals both Father and Son (¶240, 244). The nature of God’s being in time reveals the being of God in eternity. Consequently, the Catechism instructs us that Jesus’ relation to the Father reveals the eternal relation between the Father and the Son in the immanent Trinity (¶240). Similarly, “the eternal origin of the Holy Spirit is revealed in his mission in time” (¶244). The immanent Trinity is revealed by the economic Trinity. Karl Rahner, an important 20th century Catholic theologian, established a rule for thinking about the Trinity: “The economic Trinity is the immanent Trinity, and the immanent Trinity is the economic Trinity.”
3. The Trinity is unified in both being and act.
The Holy Trinity is not only unified in one divine substance (the “consubstantial Trinity”), but the Trinity is also unified in one divine mission. Each of the divine persons “is God whole and entire” (¶253). The divine being is not shared between but is rather common to each of the three persons. Similarly, each of the divine persons is involved wholly and entirely in the divine mission: “The whole divine economy is the common work of the three divine persons. For as the Trinity has only one and the same nature, so too does it have only one and the same operation” (¶258). The being and act of the Trinity are indivisible and inseparable: “Inseparable in what they are, the divine persons are also inseparable in what they do” (¶267).
God’s oneness: implications for Christian life (¶222-27)
1. We must come to know God’s glory. God is majestic and holy, and we are called to serve this one God who reigns over all creation.
2. We must live in thanksgiving. If God is one, then everything else comes directly from him and him alone. We must be ever grateful and thankful to God for all that he provides.
3. We must acknowledge the unity of all humanity. If God is one and no one else is God, then in comparison to him, all humanity is equal. We are all equally unworthy of God’s grace and equally dignified by God who created us in his image.
4. We must make good use of creation. Since all of creation comes from God but is not God, we must recognize the dignity and worth of creation. We must use everything in accordance with the fact that God alone is God, which means caring for the world around us, always discerning when things can help bring us closer to God and when things might turn us away from him.
5. We must trust God at all times. Since the one God rules over all things, we must trust God alone for all things and at all times.
The language of faith: understanding what it means to talk about God (cf. ¶239)
1. God transcends human language.
When we speak about God, we must always be aware that our words are always in themselves inadequate to speak about God. This does not invalidate all talk about God, but it means that we need to let God define our language, rather than try to make our language define God. This is especially important when we use male or female imagery. The Bible uses both male and female language to talk about God, and we traditionally use the male pronoun to talk about God. But we must remember the statement from the Catechism: “God transcends the human distinction between the sexes. He is neither man nor woman: he is God” (¶239). Our human language is gendered, but that doesn’t mean God is gendered.
2. All language about God depends upon analogy.
Our language about God is not literally or univocally descriptive of God, nor is it doubtfully or equivocally descriptive of God. Our language describes God analogically. An analogy has both similarity and difference. There is both likeness and unlikeness when it comes to our language about God. The primary rule is that God defines what language is proper to God. The difference does not consist in the fact that God is unlike us, but that we are unlike God. In the same way, the similarity does not consist in that we are similar to God, but that God is similar to us.
The divine attributes in the Catechism
1. God is one (¶200).
2. God is triune ¶202).
3. God is living (¶205).
4. God is “I AM” (¶206).
5. God is hidden (¶206).
6. God is faithful (¶207, 211-12).
7. God is holy (¶208).
8. God is merciful and gracious (¶210).
9. God is unique (¶212).
10. God is the fullness of being (¶213).
11. God is truth (¶215).
12. God is love (¶218-21).
Appendix: A Survey of the First Seven Ecumenical Councils
1. Council of Nicaea (325) lasted two months and twelve days. Three hundred and eighteen bishops were present. Hosius, Bishop of Cordova, assisted as legate of Pope Sylvester. The Emperor Constantine was also present. To this council we owe The Creed (Symbolum) Of Nicaea, defining against Arius the true Divinity of the Son of God (homoousios), and the fixing of the date for keeping Easter (against the Quartodecimans).
2. First Council of Constantinople (381), under Pope Damasus and the Emperor Theodosius I, was attended by 150 bishops. It was directed against the followers of Macedonius, who impugned the Divinity of the Holy Ghost. To the above-mentioned Nicene creed it added the clauses referring to the Holy Ghost (qui simul adoratur) and all that follows to the end.
3. Council of Ephesus (431), of more than 200 bishops, presided over by St. Cyril of Alexandria representing Pope Celestine l, defined the true personal unity of Christ, declared Mary the Mother of God (theotokos) against Nestorius, Bishop of Constantinople, and renewed the condemnation of Pelagius.
4. Council of Chalcedon (451): 150 bishops under Pope Leo the Great and the Emperor Marcian defined the two natures (Divine and human) in Christ against Eutyches, who was excommunicated.
5. Second Council of Constantinople (553), of 165 bishops under Pope Vigilius and Emperor Justinian I, condemned the errors of Origen and certain writings (The Three Chapters) of Theodoret, of Theodore, Bishop of Mopsuestia and of Ibas, Bishop of Edessa; it further confirmed the first four general councils, especially that of Chalcedon whose authority was contested by some heretics.
6. Third Council of Constantinople (680-681), under Pope Agatho and the Emperor Constantine Pogonatus, was attended by the Patriarchs of Constantinople and of Antioch, 174 bishops, and the emperor. It put an end to Monothelism by defining two wills in Christ, the Divine and the human, as two distinct principles of operation. It anathematized Sergius, Pyrrhus, Paul, Macarius, and all their followers.
7. Second Council of Nicaea (787) was convoked by Emperor Constantine VI and his mother Irene, under Pope Adrian I, and was presided over by the legates of Pope Adrian; it regulated the veneration of holy images. Between 300 and 367 bishops assisted.
For more on the Councils of the Church, click here.
