The term “Monarchianism” (according to Tert.
vanissimi isti monarchiani, “these most vain Monarchians”) is applied to several doctrines, concepts, and movements, especially from the 2nd and 3rd centuries CE, which have in common that they reject any distinction of persons or ὑποστάσεις/
hypostaseis (hypostases) within the divine essence (e.g. the duality of God and his
logos). Usually Monarchianism is differentiated into two types: 1. “Adoptionism”, which declares Jesus to be a mere man, and 2. “Modalism”, which teaches that God the Father and Son (and Hol…