By John MacArthur
It can be easy to forget how destructive sin is—not just in terms of eternity, but in our everyday lives. We’ve seen plenty of examples of how unaddressed sin routinely destroys families, friendships, and careers. But it also has devastating internal results, like robbing you of your joy and assurance, stifling your spiritual growth, and distancing you from the fellowship of God’s people.
It also pollutes and ruins your conscience.
It is possible to virtually nullify the conscience through repeated abuse. Paul spoke of people whose consciences were so convoluted and corrupted that their “glory is in their shame” (Philippians 3:19; cf. Romans 1:32). Both the mind and the conscience can become so defiled that they cease making distinctions between what is pure and what is impure (cf. Titus 1:15).
After so much violation, the conscience finally falls silent. Morally, those with defiled consciences are left flying blind. The warning signals may be gone, but the danger certainly is not; in fact, the danger is greater than ever.
Furthermore, even the most defiled conscience will not remain silent forever. When we stand in judgment, every person’s conscience will side with God, the righteous Judge. The worst sin‑hardened evildoer will discover before the throne of God that he has a conscience which testifies against him.
It is the Christian’s high and holy duty to guard the purity of his regenerated conscience. Paul had much to say about this. Note how he spoke of the conscience in the following verses (emphasis added):
“Paul, looking intently at the Council, said, ‘Brethren, I have lived my life with a perfectly good conscience before God up to this day’” (Acts 23:1).
“In view of this, I also do my best to maintain always a blameless conscience both before God and before men” (Acts 24:16).
“The goal of our instruction is love from a pure heart and a good conscience and a sincere faith” (1 Timothy 1:5).
“Fight the good fight, keeping faith and a good conscience” (1 Timothy 1:18-19).
“I serve [God] with a clear conscience the way my forefathers did” (2 Timothy 1:3).
One of the basic qualifications for deacons, Paul told Timothy, is “holding to the mystery of the faith with a clear conscience” (1 Timothy 3:9).
A pure conscience is essential not only for what it does for oneself, but for what it says to others. A sound conscience is the heart of a strong testimony for Christ. Paul frequently pointed to his conscience as a witness: “For our proud confidence is this, the testimony of our conscience, that in holiness and godly sincerity, not in fleshly wisdom but in the grace of God, we have conducted ourselves in the world, and especially toward you” (2 Corinthians 1:12). “We have renounced the things hidden because of shame, not walking in craftiness or adulterating the word of God, but by the manifestation of truth commending ourselves to every man’s conscience in the sight of God” (2 Corinthians 4:2).
Peter also wrote about the value of a pure conscience. “Keep a good conscience so that in the thing in which you are slandered, those who revile your good behavior in Christ may be put to shame” (1 Peter 3:16).
A clear, potent conscience is a vital part of your spiritual growth and your witness to others. To work properly, it cannot be hindered or corrupted by unchecked sin and unaddressed guilt.
Tomorrow we’ll look at how to clear your conscience—and how to keep it clear.
(Adapted from The Vanishing Conscience.)