"I would not be the sport and prey of wild, vain, foolish, and worse imaginations; but this evil is present with me; my heart is like a highway, like a city without walls or gates. Nothing so false, so frivolous, so absurd, so impossible, or so horrid, but it can obtain access, and that at any time, or in any place: neither the study, the pulpit, nor even the Lord's table, exempts me from their intrusion. I sometimes compare my words to the treble of an instrument, which my thoughts accompany with a kind of bass, or rather anti-bass, in which every rule of harmony is broken, every possible combination of discord and confusion is introduced, utterly inconsistent with, and contradictory to, the intended melody. Ah! what music would my praying and preaching often make in the ears of the Lord of Hosts, if He listened to them as they are mine only! By men, the upper part only (if I may so speak) is heard; and small cause there is for self-gratulation, if they should happen to commend, when conscience tells me they would be struck with astonishment and abhorrence could they hear the whole." John Newton.
John Newton, wonderfully saved from a life of great evil, involved in the slave trade, which no doubt left him with such gratitude to God for such miraculous mercy: doubtless left him with soul scars that a person who lived without such violence and evil, can scarcely imagine. In this book called "Voice of the Heart", I sense his deep humility and I can relate to all he says; especially the last line, as my sins were as scarlet as well.
P.S. If you haven't seen the fairly recent movie "Amazing Grace", you missed a good one.
Picture from the internet.