By the close of the 20th century, the idea of the church as communion had become the dominant ecclesiological model, as reflected in denominational statements and ecumenical documents. Though it is difficult to specify the characteristics of a communion ecclesiology, this view of the church tends to: (1) underwrite ecclesial communion with a certain understanding of inter-trinitarian communion, (2) emphasize the hierarchal and institutional aspects of the church, and (3) privilege Eucharist as the primary Christian practice. Little that communion ecclesiologies offer is objectionable. I argue, however, that communion ecclesiologies tend to present the church itself as the subject of eschatological perfection, rather than the Spirit-activated relational capacities and practices of human beings, which reflect and provisionally instantiate the promise of eschatological fullness. True communion is more than a specific construal of trinitarian relationships, a particular view of church organization and polity, or the observance of one Christian practice. I focus on this “more” and the real-world effects that flow from it. I contend that a deeply eschatological, relational, and practice-based vision of the church is more biblically and theologically sound than most communion ecclesiologies, and results in a more profound and transformative engagement with the world. My dissertation explores the ecclesiologies of John Milbank and John Zizioulas, analyzing each in their eschatological, relational, and practical dimensions, demonstrating how their deficiencies in these areas have concrete effect upon the manner in which Christian community, or church, is instantiated and practiced. Against this, I offer a constructive theological position, asserting that a sensitive treatment of church as an eschatological community seeking to manifest a new mode of relationality through its concrete practices opens the way for richer modes of discipleship within ecclesial communities.