Apatheia, freedom from passion, was a Stoic ideal adopted by Christian monastic writers such as Evagrius, for whom it is the health of the soul, the fruit of ascetic practice and the gateway to love and pure prayer. It does not mean indifference but a peace no longer shaken by disordered desire.
Apatheia
Dispassion: freedom from disordered passions, a calm in which love becomes possible.
Also: dispassion