“You must have light and heat, sermon plus preaching. Light without heat never affects anybody; heat without light is of no permanent value. It may have a passing temporary effect but it does not really help your people and build them up and really deal with them. What is preaching? Logic on fire! Eloquent reason!”
If one thousand preachers were asked who famously said that preaching was “logic on fire,” I suspect that one thousand preachers would say one of two things: either, “I don’t know,” or, “D. Martin Lloyd-Jones.” Lloyd-Jones did in fact say those words. He offered this description of preaching in his lectures on homiletics delivered at Westminster Theological Seminary, Philadelphia in 1969. But he was not the first to describe preaching that way!
The trailer for the Media Gratiae film, “Logic on Fire: The Life and Legacy of Dr. Martyn Lloyd-Jones,” begins with a head shot of R.C. Sproul saying that, “Martyn Lloyd-Jones was to 20th century England what Charles Spurgeon was to 19th century England.” I think, especially given the title of the biopic, that a more apropos introductory sentence would be difficult to find. It is likely the case that the very phrase “logic on fire” evidences the influence of Spurgeon on Lloyd-Jones.
Lloyd-Jones held Spurgeon’s work as a preacher in high regard. In his Westminster lecture “The Preacher,” he recommends three men whose sermons should be read: Spurgeon, Whitefield, and Edwards. Lloyd-Jones’ distinctive habit of preaching an evangelistic message every Sunday evening finds its antecedent in Spurgeon’s own practice. In his Lectures to My Students, Spurgeon notes his practice of seeking “the edification of the saints in the morning discourse” but recommends that his pupils vary that on occasion and “let the unconverted sometimes have the chief labour [sic] of [their] preparation and the best service of the day.”
Here is something else that Spurgeon said in that very same lecture:
The class requiring logical argument is small compared with the number of those who need to be pleaded with by way of emotional persuasion. They require not so much reasoning as heart argument which is logic set on fire. You must argue with them as a mother pleads with her boy that he will not grieve her, or as a fond sister entreats a brother to return to their father’s home and seek reconciliation: argument must be quickened into persuasion by the living warmth of love. Cold logic has its force, but when made red hot with affection the power of tender argument is inconceivable. ..Brethren, we must plead.”
Is the original source of this great definition of preaching important? Perhaps – it is certainly interesting to me! But the lessons that can be drawn from it are of far greater significance. Every Lloyd-Jones has his Spurgeon. Great artists, scientists, teachers, athletes… all have their influences. Sometimes the degree of the mentor’s influence is not noted by the successor – or even noticed by others. But it is nonetheless real. And who knows what God will use in the context of that relationship – whether it is mediated by personal interactions or literary remains? One gets the impression from reading Spurgeon that the phrase “logic set on fire” as the antidote to cold or merely warm preaching is yet a another example of his literary brilliance – a passing metaphor that occupied its two seconds of time and one inch of type, after which Spurgeon may have never given the phrase another thought if he remembered it at all. And yet for some reason Lloyd-Jones culminates a one hundred page, three lecture long definition of preaching with that very image. And the hearts and minds of preachers around the world have been more humbled and inspired by Lloyd-Jones’ echo than by Spurgeon’s first shout.
Speak carefully. Who knows what someone might hear from you that they will later repeat to far greater effect than you could have imagined! Whatever ministry you are called to, remember that on this side of heaven there are no throw away lines. And use the entire repertoire (Isaiah 40:1-2) of human communication in your efforts to preach the gospel of Jesus Christ.
 Llod-Jones, Preaching and Preachers (Grand Rapids: Zondervan Publishing House, 1971), p. 97.
 Ibid. p. 120.
 Spurgeon, “On Conversion As Our Aim, “ Lectures to My Students: Second Series, Lecture X (Grand Rapids: Baker Book House, p. 187.
 Ibid., p. 185.