The aftermath of a conversation can change the way we later think of its significance.

My friend — a younger minister — sat down with me at the end of a conference in his church and said: “Before we retire tonight, just take me through the steps that are involved in helping someone mortify sin.” We sat talking about this for a little longer and then went to bed, hopefully he was feeling as blessed as I did by our conversation. I still wonder whether he was asking his question as a pastor or simply for himself — or both.

How would you best answer his question? The first thing to do is: Turn to the Scriptures. Yes, turn to John Owen (never a bad idea!), or to some other counselor dead or alive. But remember that we have not been left only to good human resources in this area. We need to be taught from “the mouth of God” so that the principles we are learning to apply carry with them both the authority of God and the promise of God to make them work.

Several passages come to mind for study: Romans 8:13; Romans 13:8–14 (Augustine’s text); 2 Corinthians 6:14–7:1; Ephesians 4:17–5:21; Colossians 3:1–17; 1 Peter 4:1–11; 1 John 2:28–3:11. Significantly, only two of these passages contain the verb “mortify” (“put to death”). Equally significantly, the context of each of these passages is broader than the single exhortation to put sin to death. As we shall see, this is an observation that turns out to be of considerable importance.

Of these passages, Colossians 3:1–17 is probably the best place for us to begin.

Here were relatively young Christians. They have had a wonderful experience of conversion to Christ from paganism. They had entered a gloriously new and liberating world of grace. Perhaps — if we may read between the lines — they had felt for a while as if they had been delivered, not only from sin’s penalty but almost from its influence — so marvelous was their new freedom. But then, of course, sin reared its ugly head again. Having experienced the “already” of grace they were now discovering the painful “not yet” of ongoing sanctification. Sounds familiar!

But as in our evangelical sub-culture of quick fixes for long-term problems, unless the Colossians had a firm grasp of Gospel principles, they were now at risk! For just at this point young Christians can be relatively easy prey to false teachers with new promises of a higher spiritual life. That was what Paul feared (Col. 2:8, 16). Holiness-producing methods were now in vogue (Col. 2:21–22) — and they seemed to be deeply spiritual, just the thing for earnest young believers. But, in fact, “they are of no value in stopping the indulgence of the flesh” (Col. 2:23). Not new methods, but only an understanding of how the Gospel works, can provide an adequate foundation and pattern for dealing with sin. This is the theme of Colossians 3:1–17.

Paul gives us the pattern and rhythm we need. Like Olympic long jumpers, we will not succeed unless we go back from the point of action to a point from which we can gain energy for the strenuous effort of dealing with sin. How, then, does Paul teach us to do this?

First of all, Paul underlines how important it is for us to be familiar with our new identity in Christ (3:1–4). How often when we fail spiritually we lament that we forgot who we really are — Christ’s. We have a new identity. We are no longer “in Adam,” but “in Christ”; no longer in the flesh, but in the Spirit; no longer dominated by the old creation but living in the new (Rom. 5:12–21; 8:9; 2 Cor. 5:17). Paul takes time to expound this. We have died with Christ (Col. 3:3; we have even been buried with Christ, 2:12); we have been raised with Him (3:1), and our life is hidden with Him (3:3). Indeed, so united to Christ are we that Christ will not appear in glory without us (3:4).

Failure to deal with the presence of sin can often be traced back to spiritual amnesia, forgetfulness of our new, true, real identity. As a believer I am someone who has been delivered from the dominion of sin and who therefore is free and motivated to fight against the remnants of sin’s army in my heart.

Principle number one, then, is: Know, rest in, think through, and act upon your new identity — you are in Christ.

Second, Paul goes on to expose the workings of sin in every area of our lives (Col. 3:5–11). If we are to deal with sin biblically, we must not make the mistake of thinking that we can limit our attack to only one area of failure in our lives. All sin must be dealt with. Thus Paul ranges through the manifestation of sin in private life (v. 5), everyday public life (v. 8), and church life (vv. 9–11; “one another,” “here,” that is, in the church fellowship). The challenge in mortification is akin to the challenge in dieting (itself a form of mortification!): once we begin we discover that there are all kinds of reasons we are overweight. We are really dealing with ourselves, not simply with calorie control. I am the problem, not the potato chips! Mortifying sin is a whole-of-life change.

Third, Paul’s exposition provides us with practical guidance for mortifying sin. Sometimes it seems as if Paul gives exhortations (“Put to death…,” 3:5) without giving “practical” help to answer our “how to?” questions. Often today, Christians go to Paul to tell them what to do and then to the local Christian bookstore to discover how to do it! Why this bifurcation? Probably because we do not linger long enough over what Paul is saying. We do not sink our thinking deeply into the Scriptures. For, characteristically, whenever Paul issues an exhortation he surrounds it with hints as to how we are to put it into practice.

This is certainly true here. Notice how this passage helps to answer our “how to?” questions.

1. Learn to admit sin for what it really is. Call a spade a spade — call it “sexual immorality,” not “I’m being tempted a little”; call it “impurity,” not “I’m struggling with my thought life”; call it “evil desire, which is idolatry,” not “I think I need to order my priorities a bit better.” This pattern runs right through this whole section. How powerfully this unmasks self-deceit — and helps us to unmask sin lurking in the hidden corners of our hearts!

2. See sin for what your sin really is in God’s presence. “On account of these the wrath of God is coming” (3:6). The masters of the spiritual life spoke of dragging our lusts (kicking and screaming, though they be) to the cross, to a wrath-bearing Christ. My sin leads to — not lasting pleasure — but holy divine displeasure. See the true nature of your sin in the light of its punishment. Too easily do we think that sin is less serious in Christians than it is in non-believers: “It’s forgiven, isn’t it?” Not if we continue in it (1 John 3:9)! Take a heaven’s-eye view of sin and feel the shame of that in which you once walked (Col. 3:7; see also Rom. 6:21).

3. Recognize the inconsistency of your sin. You put off the “old man,” and have put on the “new man” (3:9–10). You are no longer the “old man.” The identity you had “in Adam” is gone. The old man was “crucified with him [Christ] in order that the body of sin [probably “life in the body dominated by sin”] might be brought to nothing, so that we would no longer be enslaved to sin” (Rom. 6:6). New men live new lives. Anything less than this is a contradiction of who I am “in Christ.”

4. Put sin to death (Col. 3:5). It is as “simple” as that. Refuse it, starve it, and reject it. You cannot “mortify” sin without the pain of the kill. There is no other way!

But notice that Paul sets this in a very important, broader context. The negative task of putting sin to death will not be accomplished in isolation from the positive call of the Gospel to “put on” the Lord Jesus Christ (Rom. 13:14). Paul spells this out in Colossians 3:12–17. Sweeping the house clean simply leaves us open to a further invasion of sin. But when we understand the “glorious exchange” principle of the Gospel of grace, then we will begin to make some real advance in holiness. As sinful desires and habits are not only rejected, but exchanged for Christ-like graces (3:12) and actions (3:13); as we are clothed in Christ’s character and His graces are held together by love (v. 14), not only in our private life but also in the church fellowship (vv. 12–16), Christ’s name and glory are manifested and exalted in and among us (3:17).

These are some of the things my friend and I talked about that memorable evening. We did not have an opportunity later to ask each other, “How are you going?” for it was our last conversation. He died some months later. I have often wondered how the months in between went in his life. But the earnest personal and pastoral concern in his question still echoes in my mind. They have a similar effect to the one Charles Simeon said he felt from the eyes of his much-loved portrait of the great Henry Martyn: “Don’t trifle!”