I have written to you before on this matter of temptation, and of course, the best thing to do is to fight it through prayer, biblical meditation, and extensive reading of the word. Negatively, we can get rid of some of the external things that tempt us, although my friend said that something must be resolved from the inside out and not outside in.

There is some truth to saying that holiness is worked from the inside out rather than from the outside in. However, without knowing more about what the Bible says, this can become misleading, so let us take some time to consider it.

Jesus says in Matthew 12:33-35, “Make a tree good and its fruit will be good, or make a tree bad and its fruit will be bad, for a tree is recognized by its fruit. You brood of vipers, how can you who are evil say anything good? For out of the overflow of the heart the mouth speaks. The good man brings good things out of the good stored up in him, and the evil man brings evil things out of the evil stored up in him.” That is, you do not change the fruit to affect the tree, but it is the tree that determines the kind of fruit that will be produced.

Then, he says elsewhere, “Are you still so dull?… Don’t you see that whatever enters the mouth goes into the stomach and then out of the body? But the things that come out of the mouth come from the heart, and these make a man ‘unclean.’ For out of the heart come evil thoughts, murder, adultery, sexual immorality, theft, false testimony, slander. These are what make a man ‘unclean’; but eating with unwashed hands does not make him ‘unclean'” (Matthew 15:16-20). By themselves, rituals, ceremonies, and religious traditions cannot make a person spiritually clean or unclean. If a person’s heart is full of unrighteousness, a mere washing of the hands will do nothing to improve his condition. Thus growth in holiness cannot consist in reforming one’s outward behavior alone.

On the other hand, the Bible refers to a put off/put on aspect of Christian sanctification. The believer casts away the bad and takes up the good. As he resists temptations and pursues holiness, he must perform the appropriate external actions.

So I tell you this, and insist on it in the Lord, that you must no longer live as the Gentiles do, in the futility of their thinking. They are darkened in their understanding and separated from the life of God because of the ignorance that is in them due to the hardening of their hearts. Having lost all sensitivity, they have given themselves over to sensuality so as to indulge in every kind of impurity, with a continual lust for more.

You, however, did not come to know Christ that way. Surely you heard of him and were taught in him in accordance with the truth that is in Jesus. You were taught, with regard to your former way of life, to put off your old self, which is being corrupted by its deceitful desires; to be made new in the attitude of your minds; and to put on the new self, created to be like God in true righteousness and holiness.

Therefore each of you must put off falsehood and speak truthfully to his neighbor, for we are all members of one body. “In your anger do not sin”: Do not let the sun go down while you are still angry, and do not give the devil a foothold. He who has been stealing must steal no longer, but must work, doing something useful with his own hands, that he may have something to share with those in need.

Do not let any unwholesome talk come out of your mouths, but only what is helpful for building others up according to their needs, that it may benefit those who listen. And do not grieve the Holy Spirit of God, with whom you were sealed for the day of redemption. Get rid of all bitterness, rage and anger, brawling and slander, along with every form of malice. Be kind and compassionate to one another, forgiving each other, just as in Christ God forgave you. (Ephesians 4:17-32)

Note the various contrasts in this passage. First, there is a fundamental difference between non-Christians and Christians. Non-Christians are characterized by “the futility of their thinking.” They are “darkened in their understanding.” But Christians have been enlightened with “the truth that is in Jesus.” Biblical sanctification, then, also aims at this fundamental level, so that Christians are to put off their old self, and to be made new in their minds, so as put on the new self (v. 22-24). Therefore, the work of the Holy Spirit in the mind, causing believers to conform and develop more and more into the image of Christ, is the very essence of sanctification.

But Paul does not stop here. This principle of sanctification works in believers to produce changes in their behavior, enabling and moving them to adopt new actions and habits. So they do not only “put off falsehood,” but now they “speak truthfully” (v. 25). They do not only avoid “unwholesome talk,” but now they speak “what is helpful for building others up” (v. 29). They do not only “get rid of…every form of malice,” but now they become “kind and compassionate to one another” (v. 31-32).

An especially illustrative contrast is Paul’s instruction to put off stealing (v. 28). To paraphrase Jay Adams, who applies this principle in counseling, “When is a thief no longer a thief? It is not when he stops stealing, since no thief steals constantly. He might be taking a break. He might even be trying to stop. But he is still a thief, and he will steal again. A thief is no longer a thief only when he stops stealing and starts working, sharing, and meeting other people’s needs. Only then can the change be genuine and permanent.” The act of stealing stems from the heart, perhaps out of covetousness or some other evil motive. Therefore, the essence of change certainly lies in the work of the Holy Spirit, applying God’s power and precept to the heart. But then the thief must actually stop stealing and start working, and he cannot start working without performing some appropriate external actions. Since this is integral to the process of sanctification, and not just the final result, these external actions are to be implemented even at the very beginning. Here is a corrective to the misunderstanding that may arise from an incomplete view of sanctification. Although sanctification is in a sense worked from the inside out, holy actions are required at the beginning as integral to the process of change. An important implication is that there is never an excuse for continuing to sin or neglecting good works.

Applying this to our own struggle against temptations, besides the inner work of the Holy Spirit, there is to be a change in our external behavior. The external change is not purely negative, but there is to be a corresponding positive development. Our focus and energy are not directed only at stopping something negative, but also at starting and continuing something positive. We do not only “put off” evil words and actions, but now we “put on” holy words and actions. So wickedness is not only abandoned, but it is replaced with righteousness, both in our thinking and in our conduct. The same principle applies when we are counseling and correcting other Christians. We must do more than to tell them to forsake sin, but we must also urge and help them to replace it, and to pursue righteousness. This will often entail some concrete external actions.

Of course, there is also the danger of bypassing inner transformation in favor of reforming the outward conduct alone, in which case no true and lasting holiness is attained, resulting in self-deception and hypocrisy. The problem occurs, however, only when we ignore part of the biblical teaching on the subject. In our passage from Ephesians, Paul makes the contrast between the basic spiritual/intellectual difference between Christians and non-Christians. His instruction to reform outward conduct is based on this foundation. We make these changes because we have come to know “the truth that is in Jesus.”

Therefore, in even speaking about this principle of sanctification to someone, we first assume regeneration, which is a sovereign act of God by which he changes the basic disposition of a person from evil to good, from a sinner to a saint, and from a child of Satan to a child of God. Of course a good tree will produce good fruit — the problem is how a bad tree can become good. Scripture teaches that this cannot be done by making the fruit good, since it is the tree that produces the fruit, and not the other way around — somehow a bad tree must become a good one. How can this be done? Can a tree change its own nature? Or, as Jeremiah 13:23 says, “Can the Ethiopian change his skin or the leopard its spots? Neither can you do good who are accustomed to doing evil.” On the other hand, “What is impossible with men is possible with God” (Luke 18:27). What is it then? True holiness becomes possible only when God sovereignly — apart from human decision and effort — chooses to change the nature of a person. And thus true holiness belongs to Christians alone, to those whom God has chosen for himself and foreordained to perform good works (Ephesians 2:10). All non-Christians remain in futility and darkness.