How does the Christian doctrine of the Trinity define God?

The Christian doctrine of the Trinity defines God as "three persons in one essence." This understanding emphasizes that God exists as a single divine essence, yet is simultaneously revealed in three distinct persons: the Father, the Son, and the Holy Spirit. Each person is fully and completely God, sharing the same divine nature, but they are not mere manifestations or modes of one another; they exist in a relationship of love and mutual indwelling.

This definition is foundational within Christian theology, reflecting the complexity and unity of the divine nature. The concept communicates the belief that while God is one in essence, the richness of God's being is expressed through the distinct roles and relationships among the three persons. Such a view underpins many key elements of Christian faith, including the understanding of salvation and the community of believers.

In contrast, the other options present views that do not align with the traditional Christian understanding of the Trinity. Defining God merely as a single entity or indicating that God has no distinct personalities does not capture the relational dynamic emphasized in Trinitarian doctrine.