Perhaps you’ve heard the joke about the rabbi who’s crossing the street in front of the church when he’s hit by a car. A priest inside hears the commotion and rushes out to lend assistance. He goes to the man, perhaps near death, and not knowing that he’s a rabbi, asks him if he believes and trusts in the Father, Son, and Holy Spirit. The rabbi, who’s far from finished, shows his mettle and responds, “I’m hit by a car, and you’re asking me riddles?” It’s an old joke, but at least I’ve never told it before: I’ve been saving it for you.
Trinity Sunday gets a bad rap, as a feast that (like the story) asks us a riddle: how can God be One and Three at the same time? For Christians, sprung from ancient Israel, and sharing in the covenant and promises of God, belief in the One God of Abraham, Isaac, and Jacob is foundational. When Isaiah, in our first reading, sees the vision in the Temple, he knows that the One appearing to him is the same God who made all things in the beginning of creation. It’s the same God who came to Moses in the burning bush and the fiery mountain and called him to his service. For Christians, belief in the One God, beside whom there is no other god, is the basis of faith.
But for Christians, faith in God as Father, Son, and Holy Spirit, is just as significant. What it adds up to is not a riddle, a theological puzzle that attempts to square the circle of three gods in one. There is only one God, but the understanding of the three Persons comes from the Christian experience of God, which is personal and relational. Far from being abstract, belief in the Trinity is rooted in the practical living of the Christian life, in the day-to-day experience of God at work in us.
In our second reading, from St. Paul’s Letter to the Romans, we see the Holy Trinity reflected in the Christian experience of prayer. Here in this letter, St. Paul is arguing for the inclusion of the gentiles in God’s promises to Israel. At one time, the gentiles had not been recognized as children of God, as inheritors of the covenant, but now they were included in the family, on the basis of adoption. God has given the Spirit equally to all peoples, incorporating them into Christ, making all of them a part of the family.
“When we cry, “Abba! Father!” it is that very Spirit bearing witness with our spirit that we are children of God” (Rom. 8:15-16). When we pray to God our Father, this cry comes from the Spirit that is at work in us. We’re not inspired by ourselves, by our own needs or wants, but by God’s will at work in us. It is the Spirit who moves us powerfully to make our needs known to God. As Paul says later in the chapter, “For we do not know how to pray as we ought, but that very Spirit intercedes with sighs too deep for words” (Rom. 8:26). The Spirit bears witness with our own spirit, as Paul says, uniting us to the life of God, bringing our wills into conformity with God’s will.
Our experience of the liturgy illustrates the point. The Spirit surrounds us and inspires us corporately as we gather in worship before God. We pray at the beginning of the Eucharist, “cleanse the thoughts of our hearts by the inspiration of the Holy Spirit.” Our gathering is inspired, and without inspiration cannot happen. The Spirit of God, the same Spirit that moved as wind over the face of the waters at the very beginning of creation, the Spirit that “blows where it chooses” (Jo. 3:8) in our Gospel today, now moves over us as we gather, inspiring our prayer to God.
If the Spirit now dwells within us, allowing us to cry “Father,” it does so because we have taken on the identity of Christ, the only Son of God. St. Paul writes in the sixth chapter of Romans that if we have been buried with Christ in baptism, we have also been raised to new life with him, through the power of his resurrection. Through baptism, we have taken on Jesus’ own identity; as Paul writes in Galatians, “It is no longer I who live, but Christ who lives in me” (Gal. 2:20).
In other words, we are incorporated into Christ through the sacraments of Holy Baptism and the Eucharist, pledges of everlasting life given by Christ himself. Again, in our liturgy, we say, “Our Father,” praying the prayer that Jesus taught us. We can do this because when God looks at us, he sees Jesus in us, the one who is alive and within us, and gives ear to our prayer.
The Spirit and the Son bring us into the presence of the Father, the source and origin of the divine Persons. The roots of Christian belief in the Holy Trinity are found in the Christian practice of prayer, and the lived experience of the three Persons themselves. The Spirit is at work in us; Christ has given himself for us. When we pray to God the Father, we do so on the ground of our identity as God’s children in Christ, inspired by the Spirit moving within us. For Christians, the doctrine of the Trinity is no abstract riddle, a puzzle to be solved. It’s the very basis of our identity, the basis of our prayer, and the basis of the new life we share in Christ.