Pilgrim's Progress §201: FAITH.

FAITH. A work of grace in the soul discovereth itself, either to him that hath it, or to standers by. To him that hath it thus: It gives him conviction of sin, especially of the defilement of his nature and the sin of unbelief, (for the sake of which he is sure to be damned, if he findeth not mercy at God's hand, by faith in Jesus Christ ). This sight and sense of things worketh in him sorrow and shame for sin; he findeth, moreover, revealed in him the Saviour of the world, and the absolute necessity of closing with him for life, at the which he findeth hungerings and thirstings after him; to which hungerings, &c., the promise is made. Now, according to the strength or weakness of his faith in his Saviour, so is his joy and peace, so is his love to holiness, so are his desires to know him more, and also to serve him in this world. But though I say it discovereth itself thus unto him, yet it is but seldom that he is able to conclude that this is a work of grace; because his corruptions now, and his abused reason, make his mind to misjudge in this matter; therefore, in him that hath this work, there is required a very sound judgement before he can, with steadiness, conclude that this is a work of grace.