The following was partly quoted and referenced from John Calvin – full reference below quote. Note: There is no talk of probabilities here. And neither should we.
From John Calvin: Institutes of the Christian Religion
5. Let it therefore be held as fixed, that those who are inwardly taught by the Holy Spirit acquiesce implicitly in Scripture; that Scripture, carrying its own evidence along with it, deigns not to submit to proofs and arguments, but owes the full conviction with which we ought to receive it to the testimony of the Spirit.73 Enlightened by him, we no longer believe, either on our own Judgment or that of others, that the Scriptures are from God; but, in a way superior to human Judgment, feel perfectly assured—as much so as if we beheld the divine image visibly impressed on it—that it came to us, by the instrumentality of men, from the very mouth of God. We ask not for proofs or probabilities on which to rest our Judgment, but we subject our intellect and Judgment to it as too transcendent for us to estimate. This, however, we do, not in the manner in which some are wont to fasten on an unknown object, which, as soon as known, displeases, but because we have a thorough conviction that, in holding it, we hold unassailable truth; not like miserable men, whose minds are enslaved by superstition, but because we feel a divine energy living and breathing in it—an energy by which we are drawn and animated to obey it, willingly indeed, and knowingly, but more vividly and effectually than could be done by human will or knowledge. Hence, God most justly exclaims by the mouth of Isaiah, “Ye are my witnesses, saith the Lord, and my servant whom I have chosen, that ye may know and believe me, and understand that I am he,” (Isa. 43:10).
Such, then, is a conviction which asks not for reasons; such, a knowledge which accords with the highest reason, namely knowledge in which the mind rests more firmly and securely than in any reasons; such in fine, the conviction which revelation from heaven alone can produce. I say nothing more than every believer experiences in himself, though my words fall far short of the reality. I do not dwell on this subject at present, because we will return to it again: only let us now understand that the only true faith is that which the Spirit of God seals on our hearts. Nay, the modest and teachable reader will find a sufficient reason in the promise contained in Isaiah, that all the children of the renovated Church “shall be taught of the Lord,” (Isaiah 54:13). This singular privilege God bestows on his elect only, whom he separates from the rest of mankind. For what is the beginning of true doctrine but prompt alacrity to hear the Word of God? And God, by the mouth of Moses, thus demands to be heard: “It is not in heavens that thou shouldest say, Who shall go up for us to heaven, and bring it unto us, that we may hear and do it? But the word is very nigh unto thee, in thy mouth and in thy heart,” (Deut. 30:12, 14). God having been pleased to reserve the treasure of intelligence for his children, no wonder that so much ignorance and stupidity is seen in the generality of mankind. In the generality, I include even those specially chosen, until they are ingrafted into the body of the Church. Isaiah, moreover, while reminding us that the prophetical doctrine would prove incredible not only to strangers, but also to the Jews, who were desirous to be thought of the household of God, subjoins the reason, when he asks, “To whom has the arm of the Lord been revealed?” (Isaiah 53:1). If at any time, then we are troubled at the small number of those who believe, let us, on the other hand, call to mind, that none comprehend the mysteries of God save those to whom it is given.
John Calvin. Institutes of the Christian Religion, I. VII. 5.
Referenced in a Kindle sample of Greg Bahnsen, Presuppositional Apologetics: Stated and Defended. Part One: Presuppositional Apologetics Positively Stated, Chapter 1, God in the Dock, Section: By What Standard.
Well worth reading the sample, and it’s free!