“To doubt God is to doubt one's own conscience, and in consequence it would be to doubt everything.”

“My principal sin is doubt. I doubt everything, and am in doubt most of the time.”

“Why is doubt the one thing we're never skeptical of? We question other peoples' beliefs, and the more sure they are the more we doubt them. But it never occurs to us to doubt our own doubt. Question our own questions. We think our questions are answers.”

“We must doubt the certainty of everything which passes through the senses, but how much more ought we to doubt things contrary to the senses, such as the existence of God and the soul.”

“Without somehow destroying me in the process, how could God reveal himself in a way that would leave no room for doubt? If there were no room for doubt, there would be no room for me.”

“Everything is false, everything is possible, everything is doubtful.”

“What anxiety when one is not sure of one's doubts or wonders: are these actually doubts?”

“Of that there is no manner of doubt—
No probable, possible shadow of doubt—
No possible doubt whatever.”

“Doubt thou the stars are fire;
Doubt that the sun doth move;
Doubt truth to be a liar;
But never doubt I love.”

“For right is right, since God is God,
And right the day must win;
To doubt would be disloyalty,
To falter would be sin.”