"When we have said these three things, then – that there is but one God, that the Father and the Son and the Spirit is each God, and the Father and the Son and the Spirit is each a distinct person – we have enunciated the doctrine of the Trinity in its completeness." – B. B. Warfield
It is an interesting fact then when Jesus said to baptize "in the name of the Father and the Son and the Holy Spirit" (Matt. 28:19) he didn't say to baptize "in the names" of the Godhead. He used the singular of onoma and not plural.
The Trinity is a very encouraging doctrine to me because it shows me that God is a God of authority and submission, fellowship and service, hierarchy and equality. I heard in my grad level humanities classes that concepts like good and evil were man made dualities that should be rejected as manipulative and illusory. Yet in my experience, those who hold this view of good and evil passionately enforce dualities like hierarchy and equality; one being "evil" and the other "good". No one uses these terms but they are upheld with religious fervor.
The God of the Bible is three persons who are equal but those persons choose various roles of submission and authority. In the same way it seems right and healthy that adults should are equal but capable of service and being served, having authority and living under it.