Loneliness expresses the pain of being alone and solitude expresses the glory of being alone.

The quote draws a sharp distinction between an unwanted condition and a chosen practice. “Loneliness” names the suffering that comes from feeling cut off—an experience of lack, abandonment, or meaninglessness. “Solitude,” by contrast, is aloneness embraced as a positive space for reflection, creativity, prayer, or self-integration. Tillich’s phrasing suggests that the external circumstance (being alone) can be the same, while the inner stance transforms it: one is passive and painful, the other active and potentially revelatory. The significance lies in reframing isolation not merely as a social deficit but as an existential and spiritual problem that can be met with courage and intentionality.