Bogomilism

Bogomilism (Bulgarian: Богомилство) was a Christian neo-Gnostic or dualist sect founded in the First Bulgarian Empire by the priest Bogomil during the reign of Tsar Peter I in the 10th century. It most probably arose in what is today the region of Macedonia as a response to the social stratification that occurred with the introduction of feudalism and as a form of political movement and opposition to the Bulgarian state and the church.

The Bogomils called for a return to what they considered to be early spiritual teaching, rejecting the ecclesiastical hierarchy, and their primary political tendencies were resistance to the state and church authorities. This helped the movement spread quickly in the Balkans, gradually expanding throughout the Byzantine Empire and later reaching Kievan Rus', Bosnia, Dalmatia, Rascia, Italy, and France-(Cathars).

The Bogomils were dualists or Gnostics (people of knowledge) in that they believed in a world within the body and a world outside the body. They did not use the Christian cross, nor build churches, as they revered their gifted form and considered their body to be the temple. This gave rise to many forms of practice to cleanse oneself through purging, fasting, celebrating and dancing.

...
Wikipedia