Living Theology #42 – The Purity and Unity of the Church

by Garrett Glende

In chapter 45 of Wayne Grudem’s Systematic Theology, he explains two characteristics of the church, namely its purity and unity. These are two distinct markers of the church when it is held up against the backdrop of the world’s culture. Specifically, “the purity of the church is its degree of freedom from wrong doctrine and conduct, and its degree of conformity to God’s revealed will.” As the above definition reflects, the church is to be pure in both its beliefs and practices, setting it apart from a world that adheres to numerous false teachings and sinful actions. Grudem also defines the unity of the church as “its degree of freedom from divisions among true Christians.” Where the world will divide over any difference it can think of, Christians are to be brought together by a common love for God and faith in Christ.

Although there will never be a perfectly pure church, the New Testament is clear that we are to strive together towards maturity and Christ-likeness. This generally comes to bear in two areas: doctrine and living. When each individual member of the church is growing in their knowledge of God and is coming to understand the truths of His Word, then holy living results. The foundation of such purity is faithfulness to preaching the whole counsel of God on Sunday mornings. Feeding the sheep with the richness of God’s word will build their understanding of God and inform them of the proper applications. Christ himself makes the purity of the church a priority. We read in Ephesians 5 that “Christ loved the church and gave himself up for her, that he might sanctify her, having cleansed her by the washing of water with the word, so that he might present the church to himself in splendor, without spot or wrinkle or any such thing, that she might be holy and without blemish.” This process of sanctification is the gradual ascent towards holiness in our daily lives. The goal of the church is to exterminate any and all sins which may harm the body and dishonor God. In this way, it sets itself apart from a world that has absolutely no concern for sin and no fear of God before its eyes.

Grudem couples this idea of the purity of the church with that of church unity. The authors of the New Testament command that believers be unified. In Philippians 2:2 Paul exhorts the church to “be of the same mind, having the same love, being in full accord and of one mind.” Elsewhere, he explains that God has gifted people in different ways so that we would be built up “until we all attain to the unity of the faith and of the knowledge of the Son of God” (Eph. 4:13). Jesus also desires that we are one so that the world would see that He was sent from the Father (John 17:20-21). Yet there is also a substantial amount of verses that speak about the necessity of separation. These portions of Scripture often deal with someone who is preaching a false doctrine about the person or work of Christ. It is the heretic or the unbeliever whom we are not to be united with. This is the principle of being unequally yoked that Paul speaks of in 2 Corinthians 6:14. This is not to say that the church is to have absolutely no interaction with the world, but only that they should not have the same type of intimate bond as they do with fellow believers. The issue of church discipline would be appropriate to bring up here, as it relates both to unity and purity, but it will be dealt with more deeply in a future chapter. However, for now it is enough to say that the church is not to have fellowship with any individual or group that does not share the same belief in the gospel of Jesus Christ.

When we consider this idea of the purity of the church, it should become quite clear that Jesus is intent on making His bride spotless and without blemish. This process towards holiness begins at the cross when He secured not only the salvation of the church, but also the sanctification of the church. It is something that is sure to take place, but it is not something that is fully left to Him. Sanctification is worked out both by God and man, but wholly under the power of the Holy Spirit. Thus, every church member plays a vital role in the purity of the body as a whole. If we continue to look at the body metaphor, then we can think of every member of the church as a different part of the body. We would not call someone with a stomach virus healthy, even if the rest of the body is in tip top shape. If a part of your body is sick, then you work hard to make it healthy. Similarly, each part of the church body must be healthy for the whole body to be truly healthy. So when we are concerned about the purity of the church, every member must take their own walks with God seriously. This means that sin must be dealt with in a serious manner. Often times it’s difficult to confess our struggles with sin to others and it is sometimes even harder to rebuke a brother or sister. But we should all be upfront about our sin in such a way that leads to more holy living. The Christian life is not meant to be lived alone. We have been baptized into a church body that is meant to watch out for the spiritual health of its members. But it takes the efforts of every member in order to truly accomplish this goal. The pastors and elders cannot be the only ones doing the work. It is everyone’s responsibility to sharpen and encourage one another so that the church would begin to look more and more like Christ.