In promoting a particular conjugal ideal, the authors of the penitentials, like many of their contemporaries, sought to circumscribe what manner, for whom, when, how, and for what purpose sexual intercourse was acceptable. In doing so, they simultaneously promoted a framework in which all sexual acts and desires not motivated by a pious, procreative intent within the bounds of lawful matrimony were deemed both deviant and sinful, according to similar parameters of time, partner, manner, and purpose. As the Ambrosian penitential expresses it, a man who committed fornication with another man or with an animal was, like one who fornicated with a woman given to Christ or married to another man, guilty of an ‘unnecessary carnal pleasure’. This general principle informs the ways the penitentials as a whole discuss the spectrum of sexual deviance involving varying degrees of physical, spiritual, and communal pollution. At one end of this spectrum are unintentional physiological responses to unbidden sexual thoughts, as well as persistent sexual fantasies. At the other are various forms of sexual contact between a parent and child, between siblings, between partners of the same sex, and with animals.

As part of a broader knowledge community, the penitentials took part in discussions about human sexuality and its consequences using ideas and conventions that crossed geographical and temporal boundaries, but did so in ways that their authors anticipated might be needed in particular places at a given time. This complicates the interplay of the social and the spiritual in defining and disciplining sexual deviance. As an aspect of human behaviour that occurs in the material world and was understood to have consequences for the soul, sexuality exposes a number of intersections between the social and the spiritual, most of which are directly related to the penitent's status and sex. Regardless of the manner of sexual deviance, however, the penitentials affirm the binary nature of early medieval gender constructions. Such distinctions would have direct implications for what might be expected of a penitent in terms of his or her sexuality. Those whose status involved sexual renunciation were held to a higher standard, and their penances reveal expectations of specialized knowledge, namely the recitation of psalms from memory.