Before their ill-fated efforts at Meaux in the 1520s, the circle of Jacques Lefèvre d’Étaples undertook a programme of ressourcement in patristic and medieval authors. They especially turned to Boethius, last of the ancients and first of the medievals, whose legacy formed the central corpus for medieval learning. Uniquely, Boethius left mathematical books that hinted at theology, and theological books that drew on mathematics – themes picked up by twelfth-century thinkers and Nicholas of Cusa. The possibility that mathematics might bridge the arts and theology fascinated these early French reformers, and they produced important editions of Boethius, the Victorines, and of course Cusanus. Pursuing the thread of the “mathematical Trinity” through some of these commentaries and editions, this chapter explains why this influential circle – like Cusanus – thought mathematics might be an essential tool in the reform of university, monastery, and even the diocese.