The late Metropolitan John of Pergamon devoted his life to fostering the unity of the Church, a commitment deeply inspired by Christ’s fervent prayer for unity in Gethsemane. His journey began with his 1965 doctoral thesis, which explored the Church’s unity in its first three centuries. This initial scholarly work set the tone for his lifelong pursuit, as he delved deeper into themes of unity, conciliarity (synodality), the Eucharist, and ecclesiastical authority in his subsequent studies. Throughout his career, Metropolitan John not only contributed to theological discourse but also actively engaged in practical efforts to realize Church unity. He was deeply involved in inter-Orthodox and inter-Christian dialogues, bringing his theological insights into practical ecclesial contexts. His work was characterized by a profound understanding of the Church’s historical and theological dimensions, always aiming to bridge gaps and foster communion among Christians.
In his groundbreaking doctoral thesis (Eucharist, Bishop, Church: The Unity of the Church in the Divine Eucharist and the Bishop during the First Three Centuries), John Zizioulas placed the concept of Church unity at the forefront of theological discourse. He began with a profound observation: “Throughout the entire period of the first three centuries, unity was bound up at the deepest level with the faith, the prayers, and the activities of the Church. St John’s Gospel reflects this fact when it presents the unity of the Church as an agonized petition in the prayer of the Lord.” Zizioulas also highlighted the emphasis on unity in the Acts of the Apostles as a defining feature of the Church’s early life.
He further noted the emergence of a “theology of unity” as early as in St. Paul’s Epistles, underscoring the Church’s foundational commitment to unity from its inception. In the post-apostolic era, unity remained a pivotal focus and an unwavering article of faith. The Apostolic Fathers treated the Church’s unity as a doctrinal principle and a goal to be actively pursued, contending with any forces of division. By the late second century, Irenaeus dedicated a significant amount of work to demonstrating the Church’s enduring oneness, arguing that unity is essential for the very existence of the Church. In subsequent generations, thinkers like Cyprian dedicated entire studies to exploring Church unity. Furthermore, various creedal texts formalized unity as a fundamental tenet of faith.
Following his thesis, John Zizioulas’ subsequent writings and studies continued to explore this theme, now through the lens of conciliarity (synodality). His numerous ecclesiological works reveal the Church’s ongoing efforts to preserve unity.
John Zizioulas’ theological exploration consistently sought to understand the implications of various realms, including Trinitarian theology, eschatology, and ecology, for the unity of Christians and the world. His anthropological reflections revealed a lamentation over individualized human nature, which inherently, from biological birth, fosters diversity marked by division rather than unity.
For Zizioulas, “otherness” was not just a characteristic but a primary ontological category, essential and constitutive of unity. He delved into the heart of theology with profound questions about the nature of divine unity: “What makes God be one?” This inquiry led him to ponder whether God’s unity was a matter of singular objectifiable existence or a relational oneness. His exploration of concepts like relational substance and oneness was groundbreaking.
In his cosmological exploration, John Zizioulas drew extensively from St. Maximus the Confessor, particularly regarding the concept of the logoi of beings. This concept posits that each being in creation possesses its unique logos, accounting for its distinct otherness. These logoi find their unity in the person of the divine Logos, leading to communion among beings and with God. Crucially, this unity does not abolish otherness but exists in tandem with it.
Zizioulas found St. Maximus’ differentiation between adiaphora (difference) and diaeresis (division) particularly significant. In his view, diaphora is an ontological characteristic, giving each being its specific identity. “Diaphora is an ontological characteristic because each being has its logos, which gives it its particular identity, without which it would cease to be itself and thus to be at all. Without diaphora there is no being, for there is no being apart from beings.”
This philosophical stance led Zizioulas to emphasize the concept of the Logos. The Logos, as the Son of the Father and not merely an intelligence or nous, unites the logoi of creation. In this unity, the individual logoi do not become part of God’s substance but retain their unique creaturely nature. Zizioulas’ studies on the theology of the Council of Chalcedon in 451 are a testament to this understanding. The Council’s formulation—that the divine and human natures are united in Christ in a Person “without confusion”—aligns with his view of unity. It suggests a communion that preserves otherness, respecting the distinctiveness of each nature while bringing them into a harmonious whole.
Zizioulas’ theological work, therefore, highlights a profound respect for the uniqueness and distinctiveness of each aspect of creation. He underscores that the unity in God’s creation does not mean a loss of individuality but rather a communion where each entity retains its identity while being part of a greater whole. This balance of unity and diversity, of the one and the many, is a central theme in his theological narrative, reflecting a deep engagement with early Christian teachings and a unique perspective on the relationship between God, creation, and humanity.
The title of one of his influential works, The One and the Many (2010) encapsulates his perspective on the complex relationship between individuality and collectivity. This theme is evident in the relational dynamics within the Holy Trinity, between Christ and the Church, and among the various expressions of the universal Church. Zizioulas emphasized that in these communal structures, there is a calling for mutual receptivity and profound interconnectedness.
In his exploration of Trinitarian theology, Zizioulas did justice to the Church’s understanding of unity, defining it as a coexistence of the one and the many. This framework allowed for a complete relationship between unity and diversity, highlighting the ontological basis of unity in the Church, which is inherently linked to multiplicity.
Addressing the complex topic of ecumenism and the vision of Christian unity, Zizioulas was adamant that unity should be tangible, eucharistic, and structured to reflect the balance of oneness and multiplicity. This structure is derived from the Eucharist, which imparts this balanced life to the Church, rooted in the very nature of God Himself. Zizioulas’ works thus offer a profound and cohesive theological perspective that integrates the individual with the communal, the one with the many, in a harmonious and divine order.
These contributions collectively underscore Metropolitan John Zizioulas’ lifelong dedication to advocating for the unity of the Church, a theme central to his theological journey. His profound insights, scholarly work, and active participation in ecclesiastical dialogues have left an indelible mark on the theological landscape. His dedication serves as a continuing source of inspiration and guidance for many who strive towards realizing the unity of the Church.
