The kinds of trinitarian discourse developed in the New Testament and in the immediately subsequent period have continued through the history of the church. With use of the triune name they are the substance of living trinitarian apprehension of God. Christians bespeak God in a triune coordinate system; they speak to the Father, with the Son, in the Spirit, and only so bespeak God. Indeed, they live in a sort of temporal space defined by these coordinates, and just and only so live “in God.” And they represent the God with whom they have thus to do, in iconography and metaphor which is functional in its attribution of deity. Where these modes lose some of their power to shape actual proclamation and prayer, as in the medieval and the modern Western church, an alienation of the church must be suspected.
Pastors often suppose the Trinity to be too complicated to explain to the laity. Nothing could be more misguided. Believers know how to pray to the Father, daring to call him “Father” because they pray with Jesus the Son, and so enter into the future these two have for them, that is, praying in the Spirit. Those who know how to do this, and who realize that just in the space defined by these coordinates they have to do with God, do understand the Trinity.