“Faith which does not doubt is dead faith.”

“Doubt isn't the opposite of faith; it is an element of faith.”

Paul Tillich (1886–1965) German-American theologian and philosopher

“Some laymen feel that, out of loyalty, they ought to cling to ancient ways of expressing the Christian faith and that to doubt is to sin. But doubt is not the enemy of faith. It is the growing edge of faith...”

Leslie Weatherhead (1893–1976) English theologian

“Love is the active, working principle in all true faith. It is its very soul, without which it is dead. "Faith works by love."”

Jonathan Edwards (1703–1758) Christian preacher, philosopher, and theologian

“She had been restless and forceful, a killer of the border hills, yet she had a childlike faith in love. She had given herself to him and never doubted the wisdom of the gift as he had sometimes doubted it. She had kept the faith, and she was dead.”

Bernard Cornwell (1944) British writer

“Sometimes I think it is my mission to bring faith to the faithless, and doubt to the faithful.”

Paul Tillich (1886–1965) German-American theologian and philosopher

“Life is doubt,
And faith without doubt is nothing but death.”

Miguel de Unamuno (1864–1936) 19th-20th century Spanish writer and philosopher

“faith without doubt is addiction”

Salman Rushdie (1947) British Indian novelist and essayist

“The opposite of faith is not doubt, it’s certainty.”

Anne Lamott (1954) Novelist, essayist, memoirist, activist

“Certainly you will have doubts. There will be questionings and faith will return again. That is how faith is established.”

Sarada Devi (1853–1920) Hindu religious figure, spiritual consort of Ramakrishna