Apatheia in the Christian Tradition

To many modern people, apatheia (being ""without suffering""/""without passion"") sounds like cold-heartedness and indifference to others, a condition to be avoided. However, in the classical world and for many in the historic Christian church it was a spiritual state to aspire to. What exactly is apatheia? What is its origin? How has it been used in spiritual writings throughout the centuries of Christian practice? And how may it help us today to articulate a Christian understanding of the...