 According to Carlo Dell'Osso, the first scholar to translate his writings into a modern language, his theology is dominated by the theme of diphysitism (a reaction to the heretical doctrine of monophysitism), which is an affirmation of the permanence and distinction of the two natures of Christ — divine and human — after the Incarnation, a condition which Leontius identified as hypostatic union.The works that comprise the "corpus leontianum" are the following; they are contained in the "Patrologia Graeca", volume 86.The first complete critical edition of these works was prepared by Brian Daley and published in 2017.