How faith should be?

The faith in spiritual things that is asked of the sadhak is not an ignorant but a luminous faith, a faith in light and not in darkness. It is called blind by the sceptical intellect because it refuses to be guided by outer appearances or seeming facts,—for it looks to the truth behind,—and does not walk on the crutches of proof and evidence. It is an intuition,—an intuition not only waiting for experience to justify it, but leading towards experience. If I believe in self-healing, I shall after a time find out the way to heal myself—if I have faith in transformation, I can end by laying my hand on and unravelling the whole process of transformation. But if I begin with doubt and go on with more doubt, how far am I likely to go on the journey?

Ref : Letters on Yoga Vol. I