The Christian doctrine of the Trinity says that God is three persons Father, Son, and Spirit in one being. Because there is only one being, there is only one God, and yet there are three divine persons. A person is something having a first-person perspective, free will, and intellect. When understood this way, the Trinity is hardly a contradictory concept. Mysterious, yes. My favorite analogy for the Trinity is that it’s like the Three-Headed Giant in Monty Python and the Holy Grail, except immaterial. The mystery comes in the case of God by how the three persons are united without sharing a physical body.