"Spiritual sickness" refers to the state of being mentally or emotionally unhealthy in our spiritual or inner selves. It often implies a lack of peace, contentment, or fulfillment in one's soul or spirit. Full definition
In Christian terminology death is the expression for the greatest spiritual sickness, and the cure is simply to die, to «die from» despair. (religion-online.org)
It is the sign of a profound spiritual sickness brought on by the wholesale dislocation of traditional values, the development of mass society, and the spectacular increase in available material power. (religion-online.org)
Viewing the soul as eternal, he sees spiritual sickness, both his own and that of others, as being more pressing than the physical. (religion.blogs.cnn.com)