Apatheia — freedom from passion or disturbing emotion — occupies a charged and contested position across the depth-psychology corpus, functioning simultaneously as a Stoic ethical ideal, a Christian ascetic goal, and a site of sharp theological controversy. In the Stoic tradition, as Sorabji meticulously documents, apatheia designated the extirpation of irrational emotion from the wise person, though the precise scope of that extirpation varied among Zeno, Chrysippus, Panaetius, and Posidonius, making the dispute at times appear — though rarely prove — merely verbal. When the term migrated into Christian monasticism, chiefly through Clement of Alexandria, Origen, and above all Evagrius Ponticus, it was refracted through a theology of grace: apatheia becomes achievable not by philosophical discipline alone but through divine gift, and it names not mere emotional blankness but a tranquil stability from which pure prayer and love (agapē) can emerge. The Desert literature complicates this ascetic optimism, insisting that the passions are fettered rather than annihilated. Latin Christianity — Lactantius, Augustine, and Jerome — mounted sustained opposition, charging that the ideal collapsed into Stoic pride and denied the moral significance of Christ’s own suffering. Cassian nevertheless reintroduced the term into Western monasticism. The tension between apatheia and metriopatheia (moderation of emotion) remains the axis around which the entire debate turns.