Below are the last four reasons for the importance of the trinity, taken from chapter 1 of Dr. Bruce Ware's book...Father, Son, & Holy Spirit: Relationships, Roles, and Relevance. The six reasons previously posted are stated without the extra thoughts, and then the last four have been added (each with part of Dr. Ware's elaboration of the reason).
TEN REASONS TO FOCUS ON THE WONDER OF THE TRINITY
1. The doctrine of the Trinity is one of the most important distinguishing doctrines of the Christian faith and therefore is deserving of our careful study, passionate embrace, and thoughtful application.
2. The doctrine of the Trinity is both central and necessary for the Christian faith to be what it is. Remove the Trinity, and the whole Christian faith disintegrates.
3. Worship of the true and living God consciously acknowledges the relationship and roles of Father, Son, and Holy Spirit.
4. The Christian's life of prayer must rightly acknowledge the roles of Father, Son, and Spirit as we pray to the Father, through the Son, in the power of the Spirit.
5. The Christian's growth in Christlikeness or sanctification is rightly understood and enriched when seen as the work of the triune God.
6. The triune relationships of the Father, Son, and Holy Spirit cause us to marvel at the unity of the triune God.
7. The triune relationships of the Father, Son, and Holy Spirit cause us to marvel at the diversity within the triune God.
The three Persons of the Godhead exhibit distinct roles in relation to one another. Distinct tasks and activities in accomplishing their common plan characterize nearly all of the work that the true and living God undertakes...The Father is the eternal Father, the Son the eternal Son, and the Spirit eternally distinct from both Father and Son. This diversity speaks of the richness of God, while never allowing the richness of differentiation to lead to discord.
8. The triune relationships of the Father, Son, and Holy Spirit cause us to wonder at the social relationality of the triune God.
God is never 'alone.' He never experiences, whether with or without the world he has made, a sense of individual isolation and 'loneliness.' He never has been lonely or alone, in this sense, nor could he ever be, even in principle. The one God is three!...In this tri-Personal relationship the three Persons love one another, support one another, assist one another, team with one another, honor one another, communicate with one another, and in everything respect and enjoy one another. They are in need of nothing but each other throughout all eternity. Such is the richness and the fullness and the completion of the social relationship that exists in the Trinity.
9. The triune relationships of the Father, Son, and Holy Spirit cause us to marvel at the authority-submission structure that exists eternally in the three Persons in the Godhead, each of whom is equally and fully God.
In this authority-submission structure, the three Persons understand the rightful place each has. The Father possesses the place of supreme authority, and the Son is the eternal Son of the eternal Father. As such, the Son submits to the Father just as the Father...exercises authority over the Son. And the Spirit submits to both the Father and the Son. This...structure of authority exists in the eternal Godhead even though it is also eternally true that each Person is fully equal to each other...
10. The doctrine of the Trinity - one God existing in three Persons in the ways we have described - provides one of the most important and neglected patterns for how human life and human relationships are to be conducted.
In the end, the doctrine of the Trinity is eminently practical, and the church can benefit much from understanding and modeling its own life, work, and relationships after the Trinity. As we understand better the nature of the Trinity...we have the opportunity to pattern what we do after God's design. We are made in the image of God, and so we can live rightly and best only when we mirror in our relationships the relationships true of the eternal God himself. Yes, we are called to be like God in character, but we also are created to be like God in relationship with one another. To miss this is to miss part of the wonder of human life, and it stems from failing to see something more of the wonder of God himself. May we see...the Trinity, the Father, Son, and Holy Spirit...and may we learn...how our relationships and work ought to be lived out, for our good and for the glory of his great and triune name.