In our Anglican Church, belief in God who revealed himself as Trinity, is fundamental to everything else about us. This is summarised in Article I of our Thirty-Nine Articles:
I. Of Faith in the Holy Trinity - There is but one living and true God, everlasting, without body, parts, or passions; of infinite power, wisdom, and goodness; the Maker, and Preserver of all things both visible and invisible. And in unity of this Godhead there be three Persons, of one substance, power, and eternity; the Father, the Son, and the Holy Ghost.
This one substance, three persons description of who God is, comes from what we find in the bible. Though the descriptive word “Trinity” isn’t used, it is the term we use to describes what the bible describes and reveals in various places. For example:
There is one body and one Spirit, just as you were called to one hope when you were called; one Lord, one faith, one baptism; one God and Father of all, who is over all and through all and in all. (Eph 4:4-6)
May the grace of the Lord Jesus Christ, and the love of God, and the fellowship of the Holy Spirit be with you all. (2 Cor 13:14)
These wonderful truths humble us and lead us to pray:
Heavenly Father, you sent your Word to bring us truth and your Spirit to make us holy. Through them we come to know the mystery of your life. Help us to worship you, one God in three Persons, by proclaiming and living our faith in you. Grant this through our Lord Jesus Christ, your Son, who lives and reigns with you and the Holy Spirit, one God, for ever and ever. Amen. (Collect for Trinity Sunday)