Irenaeus made a significant contribution to epistemology, psychology, and asceticism in late antiquity by establishing the first fully developed Christian framework for ascetic training that has come down to us. Irenaeus innovated in epistemology and psychology to direct the daily, embodied ascetic practices that enabled human beings to make progress towards union with God. Irenaeus developed an empirical epistemology from his physics of creation ex nihilo that focused ascetic training on structuring embodied perceptions in order to develop the ability to accurately discern the truth and to reliably choose the good. He produced a holistic psychology from his physics of embodiment that focused on training the soul to grasp the truth, have virtuous emotions, choose righteous actions, and follow the desires of the Spirit. Irenaeus taught that practising the ascetic disciplines of vigilant attention, meletē, and egkrateia every day was essential for structuring perception to grasp the essence of phenomena ‘as they are’, unveiling the true value of faith, righteousness, and union with God as the highest human good, and living an embodied life capable of enjoying the good without end.

The catechumenate emerged in the late second century during the period when Christianity was transitioning from a loose collection of school churches to a more unified monepiscopate. Irenaeus’s writings bear witness to the aesthetic character of knowledge in early Christian catechetical teaching during this time. For Irenaeus, the rule of truth serves as a pedagogical tool enabling new Christians to perceive the unity of creation and Scripture. This chapter looks at catechetical terminology and appeals to the Rule of Truth in Aduersus haereses and the Demonstratio.

This chapter surveys some of the key themes in epistemology and pedagogy in antique philosophical and classical education and early Christianity that illuminate the rise of Christian catechesis. Critical topics include the role of memory and the use of regula or “canons” of truth and the emergence of teachers and “school churches” in second-century Rome.