Initiatives intended to support and advance the "scholarship of teaching" have become common in Canada as well as internationally. Nonetheless, the notion of a scholarship of teaching remains contested and has been described as under-theorized. In this conceptual study, I contribute to the ongoing "theory debate" in the scholarship of teaching, applying a philosophical lens. I propose that Alasdair MacIntyre's account of "practices," including concepts of "virtue," "standards of excellence," "internal goods," and "transformation," offers a useful theoretical framework by which to identify the nature and defend the purposes and desired outcomes of this domain of scholarship. I argue that the moral virtues of justice, courage, and truthfulness, identified by MacIntyre as fundamental to all social practices, are essential also for meaningful engagement in the practice of the scholarship of teaching, but that two additional and overarching virtues are needed: authenticity and "phronesis."