When I expound Holy Scripture, I must always make this my rule: That those who hear me may receive profit from the teaching I put forward and be edified unto salvation. If I have not that affection, if I do not procure the edification of those who hear me, I am a sacrilege, profaning God's Word.
—John Calvin, Sermon on 2 Tim. 3:16–17, cited in T. H. L. Parker, Calvin's Preaching (Edinburgh: T&T Clark, 1992), 11–12.

When I go up into the pulpit it is not only to teach others. I do not withdraw apart; for I must be a scholar and the word proceeding out of my mouth should be of service to me as well as to you; or woe to me!
—John Calvin, Sermon on Job 26:4, cited in T. H. L. Parker, Calvin's Preaching (Edinburgh: T&T Clark, 1992), 40.

May the Holy Spirit grant us such affections and such effect.

In reading Tertullian's "On Baptism" (ch. 2) I was blown away by the following quote, in which he speaks of the ordinary means of water being used for the extraordinary use of God as a means of grace. At the end he quotes Paul's words from 1 Cor. 1:18ff.
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There is absolutely nothing which makes men's minds more obdurate than the simplicity of the divine works which are visible in the act, when compared with the grandeur which is promised thereto in the effect; so that from the very fact, that with so great simplicity, without pomp, without any considerable novelty of preparation, finally, without expense, a man is dipped in water, and amid the utterance of some few words, is sprinkled, and then rises again, not much (or not at all) the cleaner, the consequent attainment of eternity is esteemed the more incredible. I am a deceiver if, on the contrary, it is not from their circumstance, and preparation, and expense, that idols’ solemnities or mysteries get their credit and authority built up. Oh, miserable incredulity, which quite denies to God His own properties, simplicity and power! What then? Is it not wonderful, too, that death should be washed away by bathing? But it is the more to be believed if the wonderfulness be the reason why it is not believed. For what does it behoove divine works to be in their quality, except that they be above all wonder? We also ourselves wonder, but it is because we believe. Incredulity, on the other hand, wonders, but does not believe: for the simple acts it wonders at, as if they were vain; the grand results, as if they were impossible. And grant that it be just as you think sufficient to meet each point is the divine declaration which has fore-run: “The foolish things of the world hath God elected to confound its wisdom;” and, “The things very difficult with men are easy with God.” For if God is wise and powerful (which even they who pass Him by do not deny), it is with good reason that He lays the material causes of His own operation in the contraries of wisdom and of power, that is, in foolishness and impossibility; since every virtue receives its cause from those things by which it is called forth.

"The outbreak of war in 1562 was the culmination of a decade of extraordinary growth in French Protestantism. There may have been two million adherents in around a thousand congregations by 1562, while in the early 1550's there had been only a handful of secret groups...How had such rapid expansion taken place? Public preaching had not been possible on a significant scale to spread the messgae in France; there had not been enough ministers, and limited opportunities to gather to listen to sermons. Books played major part, but the two central texts, the Bible and Calvin's Institutes, were bulky and expensive...The explanation for this mass lay activism may lie in the one text which the Reformed found perfectly conveyed their message across all barriers of social status and literacy. This was the Psalter, the book of the 150 Psalms, translated into French verse, set to music and published in unobtrusive pocket-sized editions...In the old Latin liturgy the psalms were largely used in monastic services and in private devotional recitation. Now they were redeployed in Reformed Protestantism in this metrical form to articulate the hope, fear, joy and fury of the new movement. They became the secret weapon of the Reformation not merely in France but wherever the Reformed brought new vitality to the Protestant cause...The metrical psalm was the perfect vehicle for turning the Protestant message into a mass movement capable of embracing the illiterate alongside the literate...The words of a particualr psalm could be associated with a particular melody; even to hum the tune spoke of the words behind it, and was an act of Protestant subversion...The psalms could be sung in worship or in the market-place; instantly they marked out the singer as a Protestant, and equally and instantly united a Protestant crowd in ecstatic companionship just as the football chant does today on the stadium terraces."

-- Diarmaid MacCulloch, The Reformation (New York: Penguin, 2003), 307-8.