“This witness is true. Wherefore rebuke them sharply, that they may be sound in the faith” (Tit.1:13) “But speak thou the things which become sound doctrine:” (Tit.2:1) “Sound speech that cannot be condemned; that he that is of the contrary part may be ashamed, having no evil thing to say of you.” (Tit.2:8)
“As sound as a dollar,” was how the saying went, but you don’t hear it much anymore, for obvious reasons. You may hear some enterprise advertising itself as being a sound investment, and I suppose they still begin wills with the phrase, “So–and-so, being of sound mind, etc.” It’s a good word, all the same, and as you know, I’m fond of words. “Sound” is one of those words that to me seems to say far more than its synonyms. For instance, somehow a sound body seems sturdier than a healthy one, and sound reasoning even more convincing than logical thinking. No doubt, the fact that the godly men who translated the old King James felt it expressed exactly the spirit of the text, in so many cases, is one reason that I feel so comfortable with it myself.
Paul used this adjective three times in Titus two alone. The word has several definitions for different uses, and these three passages reflect this, I think. For instance, one definition for the word is “deep and undisturbed (as in a sound sleep),” which is exactly what I see “sound in the faith” as being. It is belief in God that withstands unbiblical reasoning, unfair treatment, and unanswered questions, when the perplexities of life would threaten to overcome us. It is deep, undisturbed, sound faith the makes us understand that the God who framed the world (Heb.11:3) has framed our lives as well (Jer.29:11).
“Sound doctrine” brings to mind the definition, “based on valid reasoning; free from logical flaws” In Paul’s admonition to speak about things that rest on a foundation of sound doctrine, he seems to be warning us against wild speculation or flights of fancy that may draw a crowd, but seldom edify one saint. As I reflect now on some of the so-called “Bible teaching” I have heard over these many years, I realize that some of it was just that—wild speculation that had no real Bible basis. And I have to wonder if it was not a substitute for willingness to apply oneself to the hard work of mastering the depths of the great doctrines of the Church, as found in the Word of God. Make no mistake; the reality of God, though accepted by faith, is highly logical. And the truths about Him and His world, as found in the Bible, rest upon solid reasoning, since they originated in the mind of God. Anything else runs the risk of being less than sound.
But it would be a shame to have doctrine condemned, not because it is unsound, but because it is presented in an unsound manner. I don’t think Paul is insisting upon a spectacular vocabulary when he praises sound speech, in verse eight, only one that is adequate and appropriate. After all, a fifty dollar word is not worth a nickel if it’s used at the wrong time or with the wrong motive. The idea expressed by the verse is clothing sound, Biblical doctrine in the most becoming attire you own. In other words, our most precise, straight forward, and convincing speech should be used to assert the claims of Jesus Christ. And it should be done in such a way, says Paul, that when those who disagree with us say something harsh against us, they are inwardly ashamed of themselves, knowing nothing we have said could honestly be condemned. There is a worthy goal for all of us!
If the primary synonym given for sound is "healthy," then the Christian who exhibits all three of these—sound doctrine, sound faith, and sound speech—could be said to have a healthy spiritual life; and, indeed, the Apostle John told his friend, Gaius, that his wish for him was that both his body and his soul would be healthy and prosperous (3 Jno.2). It’s possible to have a healthy body with a shriveled soul. We should make sure our doctrine is sturdy, our faith is resilient, and our speech is impeccable.
By the way, I know what my own standard for soundness is, therefore, my ending to the old saying would be, “As sound as the integrity of God”.