For 150 years, both in England and in the American colonies, The Marrow of Theology, by William Ames, was the standard theological work for ministers. It is biblical, succinct, and well-organized. Increase Mather once said that, other than the Bible, this was the only book of theology a minister needed.
My first introduction to Puritan theology in seminary was through the reading of this book. After reading the first chapter I was hooked on Ames. I was grabbed at the outset by his definition and nature of theology. The following excerpts of that chapter are words I need to read and reread often. My penchant for dwelling only in my thought life needs to be continually challenged with full-orbed "living to God."
Here is how Ames defines theology...
"Theology is the doctrine or teaching of living to God. John 6:68, The words of eternal life; Acts 5:20, the words of this life; Romans 6:11, Consider yourselves...alive to God."
"...[it is] a discipline which derives not from nature and human inquiry like others, but from divine revelation and appointment." (Isa. 51:4; Matt. 21:25; John 9:29; Gal. 1:11-12; John 6:45)
"Since living is the noblest work of all, there cannot be any more proper study than the art of living."
"Since the highest kind of life for a human being is that which approaches most closely the living and life-giving God, the nature of theological life is living to God."
"Men live to God when they live in accord with the will of God, to the glory of God, and with God working in them." (1 Peter 4:2, 6; Gal. 2:19-20; 2 Cor. 4:10; Phil 1:20)
"This life in essence remains one and the same from the beginning to eternity." (John 3:36; 5:24)
"Living well is more excellent than living happily."
"Theology, therefore is to us the ultimate and the noblest of all exact teaching arts. It is a guide and master plan for our highest end, sent in a special manner from God, treating of divine things, tending towards God, and leading man to God. It may therefore not incorrectly be called... 'living to God'... "
-- William Ames (1576 -- 1633), The Marrow of Theology, I:1 "The Definition or Nature of Theology"
The Kindle version of Marrow is not recommended. The Labyrinth Press print edition is best.
Read more from The Marrow -- here's William Ames on faith.