The full text of this tract for believers is shown below in the KJV version.

I have a profound, unfeigned faith in the Bible. Through grace, I have been converted, enlightened, quickened, and saved by it. Through the Bible I have received the knowledge of God, to adore the perfections of Jesus—the Saviour, joy, strength, and comfort of my soul. Many have been indebted to ministers of the gospel or to friends as the means of their being brought to God—this was not my case. That work, which is always God's, was wrought in me by means of the written Word. He who knows the value of Jesus will know how precious the Bible will be to such a one as myself.

If I have failed the Bible, in nearly thirty years' of difficult and varied life and labor, I have never found it to fail me. If it has not failed for the poor and needy circumstances of time, through which we feebly pass, I am assured it will never fail for eternity: "the word of God … abideth for ever" (1 Peter 1:23).

Just as the love of God reaches even to me, applying itself to every detail of my feebleness and failure, proving to be divine by doing so, the Word of God, which reaches down even to my low estate, also reaches up to God's height, because it is from God. As Jesus came from God and went to God, so does the Book that divinely reveals Him come from and lead to Him. If received, it has brought the soul to God, for He has revealed Himself in it. Its positive proofs are all in itself. The sun needs no light to see it by.

I declare, in the fullest, clearest, and distinctest manner possible, my deep, divinely-taught conviction of the inspiration of the Scriptures. When I read the Bible, I read it as of absolute authority for my soul as God's Word. There is no higher privilege than to have communications directly from God Himself.

For nearly thirty years, my joy, my comfort, my food, and my strength have been the Scriptures received without question as the Word of God. At the beginning of that period, I was put through the deepest exercise of soul on this point. Were heaven and earth, the visible church, and man himself to crumble away, I would, through grace, hold to the Word as an unbreakable link between my soul and God. Because of what we are, I do not doubt that the grace of the Holy Spirit is needed to make the Word profitable, and to give it real authority to our souls, but that does not change what it is in itself. To be true when it is received, it must have been true before.

Here I will add, that although it requires the grace of God and the work of the Holy Ghost to give it quickening power, yet God's Word—divine truth—has a hold on the natural conscience from which it cannot escape. The light detects the wrong-doer, though he may hate the light. This is exactly what shows the wickedness of man's will in rejecting God's Word. Men resist it because it is true. Did it not reach their conscience, they would not take so much effort to get rid of it or to disprove it. Men do not arm themselves against straws, but against a sword whose keen edge is felt and feared.

The Bible speaks of grace as well as truth. It speaks of God's grace and love, Who gave His only begotten Son so that sinners like you and me might be with Him. It is His desire that we know Him deeply, intimately, and enjoy Him now; that the conscience, perfectly purged, might joy in His presence, without a cloud, without reproach, without fear. To be there in such a way, in His love, is perfect joy. The Word will tell you the truth concerning yourself, but it will also tell you the truth of a God of love, while unfolding the wisdom of His counsels.

Let me add, dear reader, that the best means by far of assuring yourself of the truth and authority of the Word of God is to read the Word itself.

—Adapted from the Preface to "Irrationalism of Infidelity" by J.N. Darby