Through our union with Christ in His death we are delivered from the dominion of sin. But we still find sin struggling to gain mastery over us, as Paul depicted so vividly: “When I want to do good, evil is right there with me” (Romans 7:21). We may not like the fact that we have this lifelong struggle with sin, but the more we realize and accept it, the better equipped we will be to deal with it. The more we discover about the strength of indwelling sin, the less we feel its effects. To the extent that we discover this law of sin within ourselves, we will abhor and fight against it.

But though believers still have this indwelling propensity to sin, the Holy Spirit maintains within us a prevailing desire for holiness (1 John 3:9). The believer struggles with the sin God enables him to see in himself. This is the picture we see in Romans 7:21, and it distinguishes believers from unbelievers who lie serenely content in their darkness.

Interpretations of Romans 7:14–25 fall into three basic groups. It is not the purpose of this book to discuss those interpretations or to decide in favor of one of them. Whatever our interpretation of Romans 7, all Christians acknowledge the universal application of Paul’s statement, “When I want to do good, evil is right there with me.”

As indicated in the previous chapter, indwelling sin remains in us even though it has been dethroned. And though it has been overthrown and weakened, its nature has not changed. Sin is still hostile to God and cannot submit to His law (Romans 8:7). Thus we have an implacable enemy of righteousness right in our own hearts. What diligence and watchfulness is required of us when this enemy in our souls is ready to oppose every effort to do good!

If we are to wage a successful war against this enemy within, it is important that we know something of its nature and tactics. First of all, the Scripture indicates that the seat of indwelling sin is the heart. “For from within, out of men’s hearts, come evil thoughts, sexual immorality, theft, murder, adultery, greed, malice, deceit, lewdness, envy, slander, arrogance, and folly. All these evils come from inside and make a man ‘unclean’” (Mark 7:21–23; see also Genesis 6:5 and Luke 6:45).

Heart in Scripture is used in various ways. Sometimes it means our reason or understanding, sometimes our affections and emotions, and sometimes our will. Generally it denotes the whole soul of man and all its faculties, not individually, but as they all work together in doing good or evil. The mind as it reasons, discerns, and judges; the emotions as they like or dislike; the conscience as it determines and warns; and the will as it chooses or refuses—are all together called the heart.1

The Bible tells us that the heart is deceitful and unsearchable to any but God alone (Jeremiah 17:9–10). Even as believers we do not know our own hearts (1 Corinthians 4:3–5). None of us can discern fully the hidden motives, the secret intrigues, the windings and turnings of his heart. And in this unsearchable heart dwells the law of sin. Much of sin’s strength lies in this, that we fight with an enemy we cannot fully search out.

The heart is also deceitful. It excuses, rationalizes, and justifies our actions. It blinds us to entire areas of sin in our lives. It causes us to deal with sin using only halfway measures, or to think that mental assent to the Word of God is the same as obedience (James 1:22).

Knowing that indwelling sin occupies a heart that is deceitful and unsearchable should make us extremely wary. We need to ask God daily to search our hearts for sin that we cannot or will not see. This was David’s prayer: “Search me, O God, and know my heart; test me and know my anxious thoughts. See if there is any offensive way in me, and lead me in the way everlasting” (Psalm 139:23–24). God’s primary means of searching our hearts this way is through His Word, as we read it under the power of the Holy Spirit. “The word of God is living and active. Sharper than any double-edged sword, it penetrates even to dividing soul and spirit, joints and marrow; it judges the thoughts and attitudes of the heart” (Hebrews 4:12). As we pray for God to search our hearts, we must continually expose ourselves to the searching of His Word.

We must be careful to let the Holy Spirit do this searching. If we try to search our own hearts, we are apt to fall into one or both of two traps. The first is the trap of morbid introspection. Introspection can easily become the tool of Satan, who is called the “accuser” (Revelation 12:10). One of his chief weapons is discouragement. He knows that if he can make us discouraged and dispirited, we will not fight the battle for holiness.

The second trap is that of missing the real issues in our lives. The deceitfulness of Satan and of our own hearts will lead us to focus on secondary issues. I recall a young man who came to talk to me about a sin problem in his life over which he had no control. But though this problem loomed overwhelmingly in his mind, there were other areas of need in his life to which he was blind. The sin he saw was hurting only himself, but the problems he didn’t see were hurting others every day. Only the Holy Spirit can enable us to see such areas to which we are blind.

The seat of indwelling sin, then, is our deceitful, unsearchable heart. A second thing we should realize is that indwelling sin works largely through our desires. Ever since his fall in the Garden of Eden, man has listened to his desires more than his reason. Desire has come to be the strongest faculty of man’s heart.2 The next time you face one of your typical temptations, watch for the struggle between your desires and your reason. If you give in to temptation, it will be because desire has overcome reason in the struggle to influence your will. The world recognizes this and makes appeals to our desires through what the writer of Hebrews calls the pleasures of sin (Hebrews 11:25).

Not all desire is evil, of course. Paul speaks of his desire to know Christ (Philippians 3:10), of his desire for the salvation of his fellow Jews (Romans 10:1), and the desire that his spiritual children grow to maturity (Galatians 4:19).

Bridges, Jerry. 1978. The Pursuit of Holiness. Colorado Springs: Navpress.

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