John Bunyan's eminent fitness to be the author of "Grace Abounding to the Chief of Sinners" does not arise from the comparative guiltiness of his own character. Judged by the standards of his own time, he was far from being the chief. But his conception of sin, its heinousness and guilt, was not revealed to him by flesh and blood but by God Himself. It was this revelation that enabled him to write this supreme classic of sacred literature. Divine revelation of sin and grace place him in the unique position he occupies of unapproached and unapproachable greatness.