According to Cosmas the Priest, Bogomil first began to preach his beliefs in Bulgaria during the reign of the Peter I of Bulgaria (927 to 969), which indicates that Cosmas must have been writing later than 969. As with Cosmas, the life of Bogomil is shrouded in mystery and what little we know of him comes from the sermons written against him. There is some uncertainty about his relationship to Jeremiah or whether they are the same person. The statement that Jeremiah was "a son (disciple) of Bogomil" may be an interpolation.
- Arnold Joseph Toynbee Constantine Porphyrogenitus and his world 1973 "that the priest Bogomil first began to preach his heresy in Bulgaria in the reign of the Emperor Peter. Since Peter reigned from 927 to 969, Cosmas must have been writing later than 969."
- Michael Frassetto Heretic lives: medieval heresy from Bogomil and the Cathars to ... 2007 p12 "The life of Bogomil is as shrouded in the mists of the past as is that of Cosmas, and, as with Cosmas, what little we know of that life comes from the sermon written against him, and from his teachings. The founder of the heresy is ..."
- Emil Ivanov Georgiev Literatura na izostreni borbi v srednovekovna Bŭlgariia 1966 - 321 Това можеше да става, докато не бяха познати произведенията на Йеремия. Днес можем да посочим убедителни факти, които говорят, че Поп Богомил и Поп Йеремия са две различни лица. Източниците добре разграничават единия от другия.
- Zdenko Zlatar The poetics of Slavdom: the mythopoeic foundations of Yugoslavia - 2007 - 494 "There is thus no question, as Emile Turdeanu points out, that "the assertion that Jeremiah was 'a son and disciple of Bogomil' is certainly an interpolation."