This book explores why the metaphor of the church as a family is insufficient. In this, Arendt's concept of action and her criticism of privatizing the public political space by viewing it as a family are engaged through Bonhoeffer's ecclesiology and political theology and Stniloae's triadology and theology of the world. The roots of the different views of Arendt and Bonhoeffer on family symbolism are traced to their distinct notions of acting. Human action becomes the central theme of the debateparticularly influenced by the Eastern Orthodox ecumenist Stniloae and his vision of the communal relationship and interactivity of human subjects, and their place in the world. Synthesizing Bonhoeffer and Stniloae, Christian calling is unfolded not only as acting for others, but also with others as Trinitarian participatory responseresponse to the words and deeds of the three divine Persons acting in communion. In being drawn into these unique relations, human beings are empowered for communal and common acting of equals participating in public-political issues. Since the family metaphor fails to articulate such acting, this study complements this symbolism with the metaphor of the church as a political community of solidarity.