In this updated edition, Michael Allen covers the main doctrines of Reformed theology and explains how those doctrines have helped to sustain the Reformed church throughout the years. He makes a clear distinction between "Reformed" and "Reformational", emphasizing both revisionary and conservative trends within the tradition.

This edition features updated chapters and whole new sections, such as an analysis of the challenges to earthy eschatology of many influential, recent Neo-Calvinists. Additionally, a new foreword considers theological developments since the first edition, situating the text within modern theological discourse.

The book covers eight major theological themes: Word of God, covenant, God and Christ, sin and grace, faith, worship, confessions and authority, and culture and eschatology. It engages a variety of Reformed confessional writings, as well as a number of individual theologians (including Zwingli, Calvin, Bullinger, Bucer, Beza, Owen, Turretin, Edwards, Schleiermacher, Hodge, Shedd, Heppe, Bavinck, Barth, and Niebuhr).
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