The article is devoted to creation of a theoretical model of the subject experiencing religious conversion. And ontology of this subject is based on a heterologous approach. Its key points are as follows: 1) The subject of conversion is seen as a double one – as having been converted (with his or her name, memory, history, identity), and as an open subject, experiencing formation. 2) Formation is unthinkable and essentially unobvious. Formation is seen from transcendental perspective, meaning inseparable from the subject (and unidentifiable by him or her) changeable conditions of its possibility. 3) The concept of singularity makes it possible to pinpoint formation as existence without essence. To exist means (among other things) to be singular. Thus at any «having become» point of conscious existence it should be admitted that there is unconscious «underground» transition work, multidimensionality, convergent and divergent series as mobile genetic conditions of conscious «I». 4) In this situation, no impact on the subject (either internal or external) can obviously be considered as neutral. Any (as little as can be) action can run multiple kinds of causal influences that simultaneously and independently from each other will generate the following ones, etc., which can eventually lead to consequences that can be considered as bifurcation for the individual subject constitution of. 5) All of the aforesaid leads to the conclusion of procedural nature of subjectivity as such. Social subject is defined, formed and reproduced by a set of specific practices (procedures) of religious tradition, or subjectivation technologies. Religious tradition practices give a subject any given methods of subjectivity attaining that involve conscious or unconscious efforts to streamline, regulate, channel affects, passions, and desires, define personal and collective identity, social status, social roles, etc. Social subject is «static», that is maintains a certain type of subject profile, as long as these practices work and reproduce its subjective configuration to a greater or lesser degree of success. Paraphrasing A. F. Losev («Religion, in the first place, is a certain kind of life») we can say that religion is a particular practice or set of practices. Their purpose is to create and maintain a certain «spiritual make-up» of a person.