Taken from Meet the Puritans, pp. 103-4.
One day, as I was passing in the field, this sentence fell upon my soul: Thy righteousness is in heaven; and methought withal I saw with the eyes of my soul, Jesus Christ, at God's right hand; there, I say, as my righteousness; so that where I was, or whatever I was a-doing, God could not say of me, He wants my righteousness, for that was just before Him. I also saw, moreover, that it was not my good frame of heart that made my righteousness better, nor yet my bad frame that made my righteousness worse; for my righteousness was Jesus Christ Himself, the same yesterday, today, and forever. Now did my chains fall off my legs indeed. I was loosed from my afflictions and irons; my temptations also fled away. Now I went home rejoicing for the grace and love of God. I lived for some time very sweetly at peace with God through Christ. Oh! methought, Christ! Christ! There was nothing but Christ that was before my eyes. I saw now not only looking upon this and the other benefits of Christ apart, as of His blood, burial, and resurrection, but considered Him as a whole Christ! It was glorious to me to see His exaltation, and the worth and prevalency of all His benefits, and that because now I could look from myself to Him, and would reckon that all those graces of God that now were green in me, were yet but like those cracked groats and fourpence-halfpennies that rich men carry in their purses, when their gold is in their trunk at home! Oh, I saw that my gold was in my trunk at home! In Christ my Lord and Saviour! Now Christ was all (Grace Abounding, paragraphs 229-32, pp. 129-31).
"John Owen said of John Bunyan, a powerful preacher and the best-known of all the Puritan writers, that he would gladly exchange all his learning for Bunyan's power of touching men's hearts." (MTP, 101).