I love this passage from The Unquenchable Flame about how John Bunyan found assurance of salvation, and how John Owen felt about Bunyan’s preaching abilities.
“In prison, Bunyan wrote directly of his own conversion in Grace Abounding to the Chief of Sinners. It gives us a highly illuminating personal example of the introspective moralism Richard Sibbes fought, and of what Bunyan found to be the answer. In it, Bunyan describes how he would despair, in his youth, when he thought of heaven and hell, believing it ‘too late for me to look after heaven; for Christ would not forgive me’. When he tried to do better, he said, ‘My peace would be in and out, sometimes twenty times a day: comfort now, and trouble presently’.
‘But one day as I was passing in the field, and that too with some dashes on my conscience, fearing lest yet all was not right, suddenly 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, is my righteousness; so that wherever 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 rightesouness worse; for my righteousness was Jesus Christ Himself, the same yesterday, and today and for ever (Heb. 13:8). Now did my chains fall off my legs indeed, I was loosed from my affliction and irons, my temptations had fled away; so that, from that time, those dreadful scriptures of God left off to trouble me now; now went I also home rejoicing, for the grace and love of God.’
It was this message that permeated all of Bunyan’s preaching, preaching that was apparently, of such high order that when Charles II referred to him as ‘that illiterate tinker prate’ in the presence of the one-time Vice Chancellor of Oxford University, John Owen, the scholar replied, ‘Please, your majesty, could I possess that tinker’s abilities for preaching, I would gladly relinquish all my learning’.“