The “one-self” and “three-self” models of Trinitarianism are terms that are often used to discuss different theological understandings of the Trinity. Let me explain the differences between them:

One-self Trinitarianism (also known as Monarchianism or Modalism): This perspective emphasizes the unity of God and suggests that the Father, Son and Holy Spirit are different modes or manifestations of the same divine being. According to this view, there is only one self or person within the Godhead, and the Father, Son and Holy Spirit are not distinct persons but different expressions or roles that God assumes at different times.

Three-self Trinitarianism (also known as Trinitarianism or Nicene Trinitarianism): This perspective, which is the orthodox Christian understanding, maintains that the Father, Son and Holy Spirit are distinct persons within the Godhead while sharing the same divine essence. They are seen as co-eternal and co-equal, with each person having their own individuality, yet fully united in one God. This view emphasizes both the unity and diversity within the Trinity.

The main difference between one-self and three-self trinitarianism lies in their understanding of the relationship between the Father, Son, and Holy Spirit. One-self trinitarianism sees them as different modes or expressions of one divine being, while three-self trinitarianism views them as distinct persons within the one God. It’s important to note that three-self trinitarianism is the mainstream and widely accepted understanding within most Christian traditions. Here are a few examples of historical figures or theological perspectives associated with both one-self and three-self trinitarianism:

One-Self Trinitarianism (Modalism):

  • Sabellius: Sabellius was an early Christian theologian who advocated for the idea that the Father, Son and Holy Spirit are merely different manifestations or modes of one God. He believed that God operated in different modes throughout salvation history but did not consider them as distinct persons.
  • Oneness Pentecostalism: This is a modern Christian movement that subscribes to the belief in one-self trinitarianism. Oneness Pentecostals emphasize the oneness of God and reject the traditional notion of three distinct persons in the Trinity. They typically understand the Father, Son, and Holy Spirit as different manifestations or roles of one God.

Three-Self Trinitarianism (Nicene Trinitarianism):

  • Athanasius: Athanasius was an influential theologian and bishop in the early Church who staunchly defended the orthodox understanding of the Trinity. He argued for the co-equality and co-eternity of the Father, Son, and Holy Spirit, asserting that they are distinct persons within the Godhead while being of the same essence.
  • Nicene Creed: The Nicene Creed, formulated during the First Council of Nicaea in 325 AD, is a foundational statement of Christian belief that affirms the three-self Trinitarian understanding. It acknowledges the Father, Son, and Holy Spirit as distinct persons who are united in one God, sharing the same substance or essence.
  • The Cappadocian Fathers: Basil the Great, Gregory of Nyssa, and Gregory of Nazianzus, collectively known as the Cappadocian Fathers, played significant roles in articulating and defending the orthodox understanding of the Trinity. They elaborated on the distinction between the persons of the Trinity while upholding their unity and equality.

These examples represent historical figures, movements, and theological perspectives associated with either one-self or three-self trinitarianism. It’s important to note that theological discussions and interpretations of the Trinity have been ongoing throughout history, and there may be variations and nuances within each perspective. The belief about the nature of the Trinity, whether it is a one-self or three-self trinitarian model, is significant within Christian theology for several reasons:

Orthodoxy and Christian Identity: The belief in the Trinity is central to orthodox Christian theology and has been foundational to the Christian faith for centuries. Understanding and affirming the correct understanding of the Trinity is often seen as a marker of orthodox Christian identity.

Scriptural Interpretation: Different understandings of the Trinity can lead to variations in the interpretation of biblical passages that discuss the relationship between the Father, Son, and Holy Spirit. Theological perspectives on the Trinity can influence how individuals and communities interpret and understand the biblical teachings related to God’s nature.

Worship and Devotion: Beliefs about the Trinity can impact how individuals and communities approach worship and devotion. It shapes the way Christians address God, relate to Jesus Christ, and understand the work of the Holy Spirit. The liturgical practices, prayers, hymns, and doctrines associated with the Trinity often reflect the theological understanding embraced by a particular community.

Christology and Soteriology: The understanding of the Trinity has implications for how Christians understand the person and work of Jesus Christ and the process of salvation. It influences views on topics such as the incarnation, atonement, and the relationship between the divine and human natures of Christ.

Ecumenical Dialogue and Unity: Differences in trinitarian beliefs have historically been points of theological disagreement and division among different Christian traditions. Understanding and engaging with these different perspectives can be important for ecumenical dialogue and efforts toward unity within the broader Christian community.

It’s worth noting that the Trinity is a complex and mysterious doctrine, and different theological perspectives can exist within the bounds of orthodox Christianity. However, the beliefs about the Trinity are considered significant because they shape core theological concepts, influence Christian practice, and contribute to the rich tapestry of Christian thought and tradition.