From a Letter by John Newton dated April 20, 1774

My Lord,
.....Methinks the poets can have but cold comfort, when they invoke a fabled muse; but we have a warrant, a right to look up for the influence of the Holy Spirit, who ordains strength for us, and has promised to work in us.  What a comfort, what an honour is this, that worms have liberty to look up to God! and that he, the high and holy One who inhabiteth eternity, is pleased to look down upon us, to maintain our peace, to supply our wants, to guide us with his eye, and to inspire us with wisdom and grace suitable to our occasions!  They who profess to know something of this intercourse, and to depend upon it, are by the world accounted enthusiasts, who know not what they mean, or perhaps hypocrites, who pretend to what they have not, in order to cover some base designs.  But we have reason to bear their reproaches with patience.....Well, then, may the believer say, Let them laugh, let them rage, let them, if they please, point at me for a fool as I walk the streets; if I do but take up the Bible, or run over in my mind the inventory of the blessings with which the Lord has enriched me, I have sufficient amends.  Jesus is mine; in him I have wisdom, righteousness, sanctification, and redemption,—an interest in all the promises and in all the perfections of God; he will guide me by his counsel, support me by his power, comfort me with his presence, while I am here; and afterwards, when flesh and heart fail, he will receive me to his glory.
     Let them say what they will, they shall not dispute or laugh us out of our spiritual senses.  If all the blindmen in the kingdom should endeavour to bear me down, that the sun is not bright, or that the rainbow has no colours, I would still believe my own eyes.  I have seen them both, they have not.  I cannot prove to their satisfaction what I assert, because they are destitute of sight, the necessary medium; yet their exceptions produce no uncertainty in my mind; they would not, they could not, hesitate a moment, if they were not blind.....             
                                                                                                                                            John Newton