“What is truth” is a question asked by skeptics through the ages. It was asked by Pilate, the procurator of Judea, with weary cynicism, when faced with the Lord Jesus. Post Modern thinking seems to have gone further and denied that there is such thing as "truth" since we can only, in their view, make our own truth.
In the Middle Ages truth was what the Roman church said it was, or if you were in Greece or Russia it was what the Orthodox Church said it was. Wycliffe, in England challenged all this with his translation of Jerome's Latin Bible and the Lollards, and later, the Independents and the Baptists, argued that truth was what God said it was. They understood the Word of God and the Bible to be identical so everyman could find out The Truth for himself by reading the Bible. Of course there was the problem that people interpreted the Bible differently and often people failed to recognize that it was their own interpretation they quarreled over and not the actual meanings of the actual words of the Bible.
With the Renaissance came the tendency to look away from the Bible and instead to study nature both human and material. Renaissance paintings, instead of a virgin and child, a sort of ethereal goddess sort of person with an ethereal baby, depicted an ordinary young woman with an ordinary baby. Most people except the reactionaries in the churches thought this seemed sensible since this was probably how Mary and the baby probably were. In fact neither position could explain the truth of this simple "truth" of the incarnation. We still find it difficult, or impossible, at Christmas to get our heads round it and turn instead to eating, drinking, giving presents, and having a good time.
After that things really went from bad to worse. Kierkegaard, fed up with the formalism of the state church and the difficulty that religious "truth" presented to the Enlightenment mind decided that "faith" was “a leap in the dark”. In other words you did not know that God was there or anywhere, or that He existed at all but you believed. You leaped out into the void and hoped that someone was there to catch you. If there was then you at least had an experiential reason for believing. If not then, hard luck!
Meanwhile Britain was going through a period of Christian renewal. Churches and Chapels were springing up everywhere and there was a lot of enthusiasm. People claimed both a rational and an experiential reason for believing God. Nor was their leap one that was into the dark, but, lit by the light of a rational reading and application of the Bible, they set about a series of reform movements such as had never been seen before in the history of the world.
If you had asked them, a lot of those who believed and who spread the Gospel all over the world, would not have been able to give a fully coherent explanation for this enthusiasm of theirs. Some would certainly have done so. The leaders and the intellectuals among them certainly did. The Bible answered the big questions as nothing else did. On top of that it clearly demonstrated in the lives of converted criminals, drunks and losers, that it really did work in practice. When challenged as to the miracles in the Bible, one working class preacher answered, with the humor and the confidence of the British working class. “You don't believe in water being turned to wine? Then come to my house and I will show you beer turned into furniture.”
But the confidence of the nineteenth and early twentieth century evangelist was not only a pragmatic one. He also believed that there were no contradictions in the Bible. This was no leap in the dark though to some of the patronizing intellectual classes it seemed so. Our working class evangelist had read and re-read the Bible. He read it every day, morning and evening. He read it completely through, from cover to cover, often once every year, perhaps a bit more. He studied it and argued it and he took on the world in debates about it wherever people gathered to speak and to hear and to heckle.
This was a movement of power, of crude lower class language which expressed magnificently eternal truths and witnessed boldly to The Truth. Then came Darwin. At first there was uproar, but not much. Gradually the idea that the universe had come about, out of nothing, over vast aeons of time, by chance, took hold. Gradually it ate away at the convictions of the evangelicals.
The sons and daughters of the working classes were educated, some went to university and the new thinking, the modern thinking, affected them and the old ideas were leavened with the new. And the new, at first giving a certainty as of scholarship and scientific progress, finally threw all into doubt and confusion. The old ideas of truth as something which corresponded to a reality "out there" began to break down. Preachers in the churches were becoming educated men. No longer were they Bunyans, or Booths but they had the letters of University degrees after their names and people respected them as educated, better taught and of a superior intellect.