The article deals with the Messalian movement and its infl uence on three confl icts in the Greek Christian milieu of the IV–V centuries AD. The fi rst confl ict took place in Cappadocia where imperial politics in Church matters put bishop Basil in opposition to his old friend ascetic Eustathios of Sebaste. Both advocated a special type of asceticism close to the ‘Messalian’ one. The ascetics thus nicknamed appeared by the same time in Cappadocia but in the relations of the two churchmen there was no discussion of the ‘Messalian heresy’ and Basil’s type of monastic life was rather ‘Messalian’. The second confl ict arose around John Chrysostom whose background was defi nitely Syriac. His asceticism developed under the guidance of a Syrian monk Julian Sabba, who was at the same time the teacher of Adelphius, the presumed founder of the ‘heresy’. The antipathy towards the archbishop in the capital was partly due to his unusual asceticism of the same ‘Messalian’ type. For the third confl ict around Alexander the Akoiemetos in Constantinople an important testimony is the mention of an unnamed heresy in the Dialogue by deacon Palladius. Tillemont has noted once that the heresy should be clearly the ‘Messalianism’ and there is a proof of it in the treatise by Nilus of Ancyra ‘Ad Magnam’. The main charge against John, Alexander and Adelphius was irregular ascetic behaviour. The analysis of two main lists of the heretical opinions (by Epiphanius and by Theodoretus) shows that none of these was shared by the accused. Thus the opinion of Kmosko, Fitschen and Caner about the falsifi ed nature of the accusation against ‘Messalians’ gets confi rmed. The real cause of the appearance of the ‘Messalian heresy’ lies in the cultural and behavioral confl ict of the two approaches to asceticism: Greek and Syriac.