Gregory of Nazianzus (c.329-c.390) was a fourth century theologian who, along with the other so-called 'Cappadocian Fathers' (Basil of Caesarea and Gregory of Nyssa) played a large part in the theological settlement represented in the Council of Constantinople in 381 (which produced the final form of the Nicene Creed). In the years leading up to the Council, Gregory preached what have become known as the the five 'Theological Orations' in defence of the divinity of the Son, and chiefly against a group of heretics known as the Eunomians. The first oration is notable for its development of the following themes: 1. The portrayal of heretics as those who indulge in theological debate merely for 'sport' or amusement. 2. The purity of one’s heart as a prerequisite for doing theology. 3. The need for 'restraining one’s tongue' when it comes to speaking of the divine mysteries. 4. The belief that theology should be protected from becoming too 'common.' 5. The insistence that the agenda for theology should be set by its own subject matter (i.e., God) rather than by debates with opponents. 6. The plea for those interested in simply debating to focus on any subject other than God—since talking about God must always be, in a certain sense, 'dangerous.'