In this article, the Arian version of the nature of Bogomilism is considered on the example of the hagiography of St. Simeon the Myrrh-Gusher which is the first Serbian source on the history of the Bogomil heresy. Based on testimonies from other sources, the author considers the question of the origin of the Aryan interpretation of the Bogomil heresy, as well as significance of such a view for the religious policy of the rulers of Serbia from the Nemanich dynasty.