Gregory of Nazianzus

I'm reading Robert Letham's The Holy Trinity these days. Of course, Gregory of Nazianzus plays a huge role in trinitarian understanding in the history of the church, and I'm probably going to tuck into his fiveTheological Orations when I get a chance. Of them, McGuckin says,

In the subsequent history of the ancient Church these five Orations...were...adopted as the ultimate statement of Trinitarian orthodoxy despite what the conciliar creed of 381 had to say. It is a providential irony that the creed, which was itself a clear and explicit rebuke of Gregory's boldness in teaching the consubstniality of the Spirit, has come in the subsequent history of theology to be so strictly interpreted in terms of Gregory's Orations.... He could hardly have invisaged the manner in which his works would become established as the foundations of Christian orthodoxy.... For centuries after him, this sheaf of Orations became the chief trinitarian curriculum of all the Eastern schools, and of almost as great importance to the West.

The five history-making interpretations can be found here.