Between the Council of Ephesus and the Council of III Constantinople, there was a significant development of Christological doctrine. Terminology became more precise, causing the meaning of different theological words to change over time. St Cyril of Alexandria’s correct but loose “one incarnate nature,” was orthodox, but only if one understood his definition of “nature” or “phusis.” After Chalcedon, where the distinction between “phusis” and “hypostasis” had become clearer, one could no longer say “one incarnate nature” without it meaning... Read more