The purpose of this chapter is to discuss the contributions to trinitarian thought of the Reformed theologian Jürgen Moltmann and the Lutheran Wolfhart Pannenberg. To treat them together with regard to the content of their trinitarian theologies is justifiable because in spite of all their differences, these two German theologians both echo and have shaped nearly all the key themes of the doctrine of the Trinity in contemporary theology.

In order to orient the reader to the context and background of these two trinitarian theologies as well as the state of current discussion, a list of key themes follows here:

1. Following Barth and Rahner, both Moltmann and Pannenberg seek to ground the Trinity in revelation and salvation history rather than in abstract speculation.

2. Therefore, Rahner's Rule – beginning with oikonomia (God's actions in history) to speak of theologia (who and what God is) – has become a standard principle.

3. Again, following both Rahner and Barth, the “turn to history” has become one of the contemporary canons of trinitarian reflection.

4. The “turn to history” has made reflection on the relationship between the economic and immanent Trinity a focal issue.

5. Contrary to tradition, threeness is taken for granted, while the unity of God becomes the challenge.

6. Consequently, eschatology has risen to a new position of appreciation in trinitarian theology.

7. Because of the turn to the social analogy under the leadership of Moltmann, the “practical” implications of Trinity are being discussed in a fresh way.