This past weekend I had the privilege of officiating at my niece’s wedding. Standing between two old, gorgeous fir trees, with my back to a crystal blue lake, I faced my niece, her then fiancé, their friends, and their family members who gathered to surround them with love. It was a beautiful, sacred moment in time.
As I worked on putting together the service, I read through various liturgies and found myself coming back to the good ‘ole PCUSA Book of Worship. Yes, I adapted it, but I simply couldn’t find anything with a more meaningful theological foundation or a structuring of the service that represents the leaving and cleaving dimension of marriage. As I thought about the homily, I turned to Karl Barth’s Church Dogmatics. There’s been much ado about Barth’s relationship with his wife and Charlotte–his assistant, who lived and travelled with him and without whom he wouldn’t have finished as much of the Dogmatics as he did. Most assume that Barth and Charlotte were lovers; a few hold out hope that they kept their relationship platonic. Whatever the case may be, I suspect that Barth’s capacity to capture the inner, spiritual dynamic of marriage was deeply related to his own pain and perplexity.
Barth sets forth his theology of marriage through a series of dialectical pairs. Marriage is vocation and choice, gift and task, one-ness and two-ness, exclusive and inclusive, lifelong with the possibility of dissolution, and a spiritual and institutional reality.
Marriage is grounded in God’s call to two particular persons. As a calling, it is to be discerned with reverence. As a vocation, it is a response to God’s work. And that makes it a choice, and not merely one choice but a lifetime of choices for this particular other.
Marriage is a gift from God, therefore, and something to receive. It is a gift of love that two people participate in, with, and for one another. And it is a task. Entering into marriage does not automatically create a life-partnership. Marriage is work, the work of creating a common existence. Furthermore, marriage is not the means to another end, such as sexual fulfillment, creating a home, having children. Marriage as a life partnership is an end in and of itself.
Marriage is marked by togetherness and differentiation. In marriage, two become one yet without losing their two-ness, i.e., their particularity as persons. Barth writes, “In marriage one cannot even with the best intentions see hear, think, speak or live apart from one’s partner” (191). Both partners are oriented toward each other, faithfully affirming each other’s humanity. Yet this union does not subsume the identity of each. The two are still distinct. To each other, each is the OTHER. In their union, they are freed to become all that God has intended for them.
Marriage is both exclusive (monogamous) and inclusive (open to relationships with others). In marriage, two people are freed, by the grace of God and the gift of love, to belong to one another and no one else. Just as God freely elects a particular people (Israel in the OT, the Church in the NT), so two spouses choose one another exclusively. And these two belong to a larger fellowship. For marriage is hospitable. Love overflows. It cannot be hoarded. It nurtures others, and at the same time, marriage is nurtured by others. Its success depends upon fellowship with multiple communities, most especially the church. Thus the failure of any marriage is a judgment on the church and calls the church to repent.
If marriage is grounded in God’s call, if it is exclusive, and if it springs from love, then it must follow, according to Barth, that marriage is a life-partnership. It is analogous to God’s faithful, steadfast, enduring love toward creation. On the one hand, marriage is indissoluble, because it is constituted by God, not by humanity and not by any sociological institution. On the other hand, a particular marriage can be based solely on institutional procedure and human consent, devoid of God’s call. It may be a reflection of human error rather than the covenantal grace of God. Hence it can and perhaps ought be dissolved, resulting in greater peace, healing, and order for all. In such instances, the church stands under the judgment of God for having blessed inhuman marriages with its authority.
Divorce, however, ought to be undertaken only in the context of faith and only after rigorous examination, prayer, and attempts to do otherwise. In the midst of such heart-rending pain, faith enables one to hear and receive God’s judgment upon that which only appears to be marriage and thus to dissolve it legally. Barth has good news for those who are divorced. He places the question of marriage and divorce in proper relation to all matters of living as a disciple of Christ. “Much is decided in marriage, but not everything, not the ultimate thing, not the whole question of a life of salvation” (210).
Finally, marriage is both a spiritual reality and an institutional reality. The wedding ceremony declares publicly that which God has already constituted. While the institution of marriage can exist without God’s calling, God’s calling requires “public advertisement and recognition, and a definite form” (226).
My prayer for my niece and her fiancé is that they receive and live into the beauty and paradox of marriage. In fact, perhaps such a vision of marriage—one focused on its inner dynamic, its spirituality—might help reorient our ecclesial and cultural debates about marriage, pushing us to focus on strengthening and supporting all life-partnerships. 
 Karl Barth, Church Dogmatics III/4 (Edinburgh: T & T Clark, 1961).
 It should be noted that Barth wrote about marriage as between a man and a woman. He also ordered male-female relationship in marriage in ways that many of us today would find theologically untenable. I have not included those dimensions of his thought here. It is important to note, however, that at the end of his life Barth expressed a willingness to consider the fact that same-sex couples may be called to the same kind of marriage as those of the opposite sex. This would have necessitated a reconsideration of any vestiges of patriarchy in his theology of marriage as well.