This study is concerned with the development of a distinct and coherent
tradition of thought on the Trinity in the twelfth and thirteenth centuries. The strength
of this tradition was such that, in a significant number of cases, it actually prevented
theologians from being able to see the real issues before them. When theologians in
the thirteenth century come to put forward their interpretations of the statement on the
Trinity issued by the Fourth Lateran Council of 1215, they are severely hampered in
their ability to do so because of their preoccupation with an argument about the divine
essence which is, at the most, tangential in the Lateran decree itself. Their
interpretations are so wide of the mark as to constitute nothing less than a case of
collective misunderstanding.
This raises questions about rationality and hermeneutics which are not as easily
answerable as they first appear. The difficulty arises because it is just possible to
discern a conceptual link between the skewed interpretation offered by these
theologians and the issues addressed in the Lateran decree as they appear to us today.
It is almost as if theologians considered their version to be legitimate because they
saw an intrinsic link between the issues of divine unity and divine generation, the
main concerns of the decree and academic theologians respectively.
What gives credence to this possibility is that these issues were themselves
often inseparable in the development of trinitarian theology in the twelfth and
thirteenth centuries. Much of the coherence of the tradition of academic theology of
the Trinity derived from a recurrent preoccupation with the question of whether the
divine essence begets. In certain crucial instances, the answer to this question was
determined with reference to the doctrine of divine unity. The idea was that the
generation of the essence would impair irretrievably the absolute unity of essence
which was beginning to emerge as the dominant view of divine unity.
The Lateran Council's statement on the doctrine can only be understood within
this wider theological context. It is no longer possible to attribute this statement to
Pope Innocent III's wish to bolster the authority of Peter Lombard. Innocent himself
borrowed from Joachim's trinitarian theology, making it almost inconceivable that he
would have later wished to condemn the same theologian. Only by giving less
attention to the personalities involved and more to the issues themselves can we
realise the full significance of the theological controversies of this period