“As sound as a dollar,” was the old saying; but you don’t hear it much anymore, for obvious reasons. Today's dollar is about as sound as a politician's promise. No, I think we need to look elsewhere for something to which we can attach the adjective, "sound." But it’s a good word; I like it. To me, a sound body seems sturdier than a healthy one; and sound reasoning even more convincing than logical thinking. I'd rather it be said of me that I was of sound mind than that I had my wits about me. But that's just me.
"But speak thou the things which become sound doctrine" (v.1) SOUND: "based on valid reasoning; free from logical flaws; having a firm foundation; unshakeable"
Is Paul warning us here against wild speculation, flights of fancy that may draw a crowd, but fail to edify one saint of God? Undoubtedly. 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 plumbing the depths of the great, historic doctrines of the Church, as found in the Word of God.
Make no mistake; the reality of God and the Deity of Jesus Christ, though appropriated by faith, are based on revelatory logic; and the truths about Him and this world rest upon the firm foundation of a Bible that originated in the mind of God. But any so-called doctrine outside these bounds may be thought provoking, but is certainly not sound.
"That the aged men be sober, grave, temperate, sound in faith..." (v.2) SOUND: "deep and undisturbed (as in sound sleep)"
When I think of faith, this definition of the word, "sound," seems entirely appropriate. Sound faith runs deep and is undisturbed by the perplexities of life that would threaten to overcome us. It is belief in the goodness of God that keeps us from fainting (Psl.27:13) and makes us understand that the God who framed the world has framed our lives as well (Heb.11:3). Therefore, we rest, undisturbed, sound in faith.
"Sound speech that cannot be condemned..." (v.8) SOUND: "sturdy, good, fit, healthy"
Proverbs 15:4 tells us that a "wholesome" or healthy tongue is a "tree of life." What we're talking about here is speech that is uncompromising but kind (Eph.4:15); soaked in grace and seasoned with salt (Col.4:6); that never wounds without binding up (Hosea 6:1). And, by the way, we may argue, “I didn’t mean what I said,” but Matthew 12:34 argues against us. “[O]ut of the abundance of the heart the mouth speaketh." The rest of Titus 2:8 goes on to say that we should speak in such a way that when people with whom we disagree loudly condemn us, they'll feel ashamed of themselves later.
If a good synonym 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 (3 Jno.2). You see, it’s possible to have a healthy body with a shriveled soul.
So, then, what shall be our standard? As sound as....what? My answer would be "as sound as the Word of God." As the song says, "You can live by it, die by it, rest and rely on it." Consume it to possess sound, sturdy doctrine; sound, resilient faith; and sound, impeccable speech.