Trinity
The Christian doctrine of the trinity defines God as three persons, expressions or hypotheses: Father, Son, and Holy Spirit; "one God in three people". The three are different, but one "material, essence or individuality". In this context, "primacy" is "what" is something, while "person" is "who" is something. As the nature of God itself can not be described, so is this unity that is very difficult to understand because it is the secret of God himself. In conclusion this doctrine states that God is of three personalities namely God the Father, the Son of God and the Lord God of the Holy Spirit. These three persons form one Godhead.