There are two comments that I frequently hear about the doctrine of the Trinity as it relates to contemporary confessional Protestantism. One is that the doctrine is too abstract and speculative, and thus of little or no practical relevance. The other is that Protestantism is frequently little more than a functional Unitarianism: we pay lip service to the doctrine of the Trinity, but do not allow it to get in the way of going about our regular Christian business.

The two objections are both powerful, in large part because they are true—at least in terms of practical outworking. Protestantism has not traditionally placed the Trinity at the practical center of Christianity. As a result, the doctrine has become akin to the revered grandfather who is always invited to Christmas dinner, but sleeps on the couch after lunch and takes no active role in the family celebration.

How does one go about remedying such a situation? After all, the technical vocabulary of Trinitarian theology—person, hypostasis, substance, and essence—does seem to support the notion that one is dealing with a highly abstract and practically irrelevant concept.

The Trinity and Worship

To point us toward a solution to this problem, we need to understand how the doctrine of the Trinity originated. It did not arise out of philosophical discussion. Rather, the doctrine has its origins in the most basic acts of Christian worship. In baptism, explicit reference is made to the Father, the Son, and the Holy Spirit. The cry of praise, "Jesus is Lord!" if it is to make any sense at all, requires explanation in terms of the Trinitarian God. You cannot get more basic or practical than baptism and praising Jesus, and the doctrine that supports those activities should therefore never be presented in such a way that it appears dry as dust and irrelevant to a joyful Christian life.

If the doctrine of the Trinity is inextricably linked to Christian worship, then we should spend time reflecting upon its implications for our practical, devotional lives. One excellent way to do this is to read and meditate upon John Owen's great work, Of Communion with God the Father, Son, and Holy Ghost, Each Person Distinctly, in Love, Grace, and Consolation. This work, published in 1657, is perhaps the most extended examination ever written of the direct way in which the Trinity should shape the Christian's devotional thinking about God.

Owen emphasizes the three persons of God far more than the unity of the Godhead. Arguably, he overemphasizes the personal distinctions. But, given the basic Unitarian tendency in much of Protestant thinking, at least at a practical level, his emphasis can perhaps be forgiven as a necessary corrective.

Underlying Owen's treatise is a clear understanding that the Christian God is not just some "god" in a generic sense. Rather, he is particularly the one God who exists in three persons. While there are many mysterious dimensions to this truth that are beyond human comprehension (even elevated and sanctified human reason), Owen shows that the doctrine of the Trinity is clearly demanded by the biblical teaching about salvation. To know salvation is to know the actions of the God who is three and the God who is one. In no other way can sense be made of the biblical material.

Owen sees Scripture as teaching that the Father, the Son, and the Holy Spirit each play particular roles in the drama of redemption, reconciliation, and consummation. The Father appoints the Son as mediator to act as prophet, priest, and king for his people. The Son willingly takes up the office, humbles himself by taking the form of a servant, and lives, dies, and rises again as the second Adam, the representative head of a new humanity. The Spirit applies Christ's work to each of God's people at the appointed time. In addition, the Spirit works in a profound way in the life of Christ, effecting his conception, strengthening his human nature, guiding and protecting him, and finally raising him from the dead. The drama of salvation is thus richly Trinitarian, and the Christian's response of praise should therefore be framed in Trinitarian terms. This truth provides Owen with the basic structure for his treatise.

Communion with the Three Persons

First, there is communion with the Father. The particular focus for this is the Father's love. Unlike caricatures of Protestant orthodoxy which picture an angry Father somehow being mollified by his Son and persuaded to be merciful, Owen is very clear that the first person of the Trinity is, in a sense, the very fountainhead of salvation, in that his love drives the whole scheme of salvation. The primary focus in Christian devotion, when it comes to God the Father, is this: that he who created the world in righteousness, wisdom, and holiness, and then saw that world desecrated by human sin, should yet love it enough to send his Son, his only Son, the Son whom he loves, to die for the salvation of sinners.

Second, there is communion with God the Son in grace. The Son did not need to accept the office of mediator; he did not need to humble himself; indeed, he considered it not robbery to be equal with God. Yet, in his infinite grace and mercy, he condescended to take up the task set before him and to see it through to death and beyond. There is a sense, therefore, in which Jesus Christ is grace, in that he exemplifies and embodies the unconditional self-giving of God on behalf of sinners. Only when we grasp the Father's love for the Son, and the fact that the Son is also God, do we really see the full magnificence of divine condescension and grace in the work of Christ.

In this context, Owen repeatedly emphasizes not only the acts of Christ in history, but also his acts in our experience. The communion of the believer with Christ has a twofold practical, ongoing aspect. First, it is one of conjugal, or marital, relationship, and this means that the believer knows Christ in a truly profound way, and, indeed, delights in him as a heavenly spouse. The language of love, enjoyment, and beauty that Owen uses here indicates that the Christian life, as it is one of communion with Christ, is to be something truly thrilling and wonderful.

Second, there is a communion in holiness. As his death and resurrection form the basis for the believer's acceptance with God, so the Son's sending of the Spirit connects to the believer's daily growth in holiness through habitual communion with God. Union with Christ and adoption in no way eclipse the forensic nature of justification, but they do provide an important dynamic in the Christian's life and experience subsequent to justification.

Third, there is communion with the Spirit. For Owen, the Spirit is intimately connected to Christ. His primary saving significance is in the role he plays in the Incarnation: he is the agent of conception; he supports, strengthens, and enlightens Christ's human nature, from birth to death; and he raises Christ from the dead. Then, in the life of believers, he fulfills numerous further functions: he applies the words of Christ; he causes believers to glorify Christ; he sheds God's love abroad in their hearts; he gives assurance of God's favor; and he is the Spirit of adoption, whereby, in Christ, we can cry out "Abba, Father!" Every step belongs distinctly to him, but every step is also vitally connected to the work of Christ.

In laying out the believer's identity and existence in terms of the saving action of the Trinity, Owen brings to the fore why it is so crucial to have a rich understanding of the Trinity for theology, not just at a theoretical level, but also in terms of the most practical aspects of Christian devotion. Of course, all of the actions of any person of the Godhead are, in a sense, actions of all three persons, given that neither Father, Son, nor Spirit does anything without the other persons being fully on board. But it is easy to forget that each person plays a distinct role in salvation, and thus in the way we relate to God. If we carefully read and reflect upon Owen's treatise, we will realize that Trinitarianism is not too abstract to be of practical value, and then we can start to frame our Christian lives and identities in truly Trinitarian dimensions.

The author teaches church history at Westminster Theological Seminary in Philadelphia. Reprinted from New Horizons, May 2006.