Life is doubt, and faith without doubt is nothing but death.

The line encapsulates Unamuno’s existential Christianity: to be alive is to be inwardly divided, questioning, and restless. “Doubt” here is not mere skepticism but the felt tension between the hunger for meaning/immortality and the mind’s inability to secure certainty. In that sense, doubt is a sign of spiritual vitality—an ongoing struggle that keeps faith from hardening into complacent dogma. A “faith without doubt” becomes “death” because it implies a closed system with no risk, no yearning, and no living engagement with the tragic conditions of human existence. The quote elevates uncertainty as the engine of authentic belief and selfhood.