Grace Abounding to the Chief of Sinners John Bunyan - Grace Abounding to the Chief of Sinners, or a Brief Relation of the Exceeding Mercy of God in Christ to his Poor Servant John Bunyan is a Puritan spiritual autobiography written by John Bunyan. It was composed while Bunyan was serving a twelve-year prison sentence in Bedford gaol for preaching without a license and was first published in 1666.