Because you have seen me, you have believed; blessed are those who have not seen and yet have believed.
-- Yeshua ben-Yosef (attributed), on the importance of seeing the winds of evidence instead of waiting for absolute proof.
Personally, I always favored this one:
I have spoken to you of earthly things and you do not believe; how then will you believe if I speak of heavenly things? (John 3:12)
Of course, this one nicely cuts both ways.
Here's the new quotes thread.
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