We are going through the Gospel of John on Sunday evenings and have dealt with the doctrine of the Trinity. For those who would like to do further study, you are welcome to borrow any of the books I have:
Father, Son, and Holy Spirit: Relationship, Roles, and Relevance. Bruce A. Ware (Crossway, 2005; ISBN#: 0-5813-4668-9).
The Holy Trinity: In Scripture, History, Theology and Worship. Robert Letham (P&R, 2004; ISBN#: 0-8755-2000-6).
The Forgotten Trinity: Recovering the Heart of the Christian Belief. James White (Bethany House, 1998; ISBN#: 1-5566-1725-9).
Our Triune God: A Biblical Portrayal of the Trinity. Peter Toon (Victor/Bridgepoint, 1996; ISBN#: 1-5647-6553-9).
Understanding the Trinity. Alister E. McGrath (Zondervan, 1990; ISBN#: 0-3102-9681-1).
Why You Should Believe in the Trinity: An Answer to Jehovah's Witnesses. Robert M. Bowman (Baker, 1989; ISBN#: 0-8010-0981-2).
God in Three Persons. E. Calvin Beisner (Tyndale, 1984; ISBN#: 0-8423-1073-8).