This paper will examine the Nouveaux éléments de Géométrie of 1667, a seemingly unlikely intervention in the mathematical culture of the mid-seventeenth century for Antoine Arnauld, a firebrand theologian and author of works on topics in logic and grammar. The aim of this paper is to examine Arnauld’s reasons for penning a revised edition of Euclid’s Elements particularly given the hostile attitudes of fellow theologians who insisted that the practice of mathematics was a futile, trivial, and vainglorious misuse of time. In this talk I show that Arnauld created a geometry that he hoped would serve in the cultivation of moral, spiritual and intellectual virtues. In order for geometry to serve these propaedeutic goals, Arnauld believed a new edition of Euclid was required, one that was cleaved of the epistemological, methodological and mathematical confusions he thought were common in contemporary editions. The account of Arnauld’s mathematical interventions I offer connects his mathematical treatise to concerns in moral philosophy, theology and epistemology. These reflections, I argue, are indispensable to developing any account of mathematical practice in the early modern era.