EN
The article analyses the lexical means used to express the cultural concept lie in the titles against the dualistic heresies in the following sources: the Slavic translation of Panoplia dogmatics by the monk Euthimius Zigabenos, Discourse against the Bogomils by Presbyter Cosmas, and the Bulgarian translation of the Synodicon of Orthodoxy. Three semantic fields intervening to each other are referred to: the lie as a verbal act, as untruth, as hypocrisy. In the middle ages, doctrinal and religious forms of deviation from the Divine truth were the most severe form of lying. Its interpretation in different epochs and societies shows stable semantic valences. Lie is a category of the culture that has given rise to the well-established lexicon in every language.