When it comes to biographical material on Saint Augustine, in the last 50 years, no work has surpassed Peter Brown’s seminal biography, Augustine of Hippo. This biography is a formidable one, but well worth the time to walk through the life of a truly great church father. Brown addresses many episodes in Augustine’s life, but there are three that stand out as truly defining moments in both the church father’s life and the life of the church.

First, early in life, Augustine wrestles with the Manicheans over the genealogy and essence of evil. Later, he comes into conflict with the Donatists on both how to define the true church as well as what comprises the nature of a true Christian. A final defining conflict that Brown highlights is Augustine’s duel with Pelagius and his disciples concerning man’s role in salvation. Of the three, the controversy with Donatus is probably the least known, and yet it’s this one I think might be most relevant for us today.

The issue of Donatism predates Augustine by almost a century and has its origin in the Diocletian persecution. Beginning in February of 303, persecution edicts came from the hand of the emperor. What followed were restrictions on Christian gatherings, the burning of Scriptures, and the razing of churches. These persecution edicts continued for almost eight years before they were discontinued in 311 because the persecution of Christians did not have the desired effect. Instead of destroying the Christian community, persecution only strengthened their resolve and increased their numbers! While the church ended up thriving through this persecution, she did not do so unscathed. From without, she faced the wrath of Rome, and from within, she faced the betrayal of brothers. To escape persecution, some Christians betrayed their Lord and brothers and willingly handed over the sacred Scriptures to be burned and defiled by pagans. These people were labeled traditor because they “handed over” God’s word to be destroyed.

Instead of defining the true church in the way of the law, Augustine approaches the issue pastorally in the way of the gospel

As in all the eras of persecution and consequent apostasy, a question quickly arises: “Who comprises the true church?” The followers of Donatus had a very easy and logical answer to this question. Whoever did not betray their brothers and their Lord under persecution, whoever didn’t become a traditor, these were the true Christians and the true church. The purity of the Donatists was, therefore, an external purity, a visible purity, and a legal purity. They defined the true church as a product of the law, born from the law, preserved by the law, and brought to completion by the law.

Augustine inherits the problem of defining the church through means of purity from an earlier time. But instead of defining the true church in the way of the law, Augustine approaches the issue pastorally in the way of the gospel. This means Augustine pins the holiness of the church on participation in the body of Christ rather than on the lawful behavior of the Christian. It is the sanctifying rites of the church, baptism, holy communion, and absolution, which make the church holy (Eph 4:4-5). These are the gifts of the gospel, not the wages of the law. Put another way, the church is holy because she has a Holy Spirit who is working in her a holiness that is otherwise alien to her (1 Cor 12:12-14). Augustine notes with the evangelist John that the work of the Holy Spirit is not subject to geometry and the senses, but is mysterious and hidden from our eyes. The wind blows and you hear its sound, but know not whence it comes or where it goes. The same can be said of the Holy Spirit’s work through the saints (John 3:7-8). Therefore what we see of the church on earth is only a shadow of the full reality (1 John 3:2). The dividing line between the elect of God and the damned is also hidden from our eyes. To use the later language of Luther and the Bondage of the Will, the church is hidden and the saints concealed. That the church is holy is a promise of God to be apprehended not by sight, but by the hearing of faith. If we could receive it with our eyes, we wouldn’t have to confess it in the Creed.

That the church is holy is a promise of God to be apprehended not by sight, but by the hearing of faith.

Despite Augustine’s work battling the Donatist error, the nature of a true Christian is still debated today. Unfortunately, many will answer with Donatus that a particular denomination defines the true church, and, unsurprisingly, it’s usually whatever group they claim as their own! Yet as Augustine shows through Scripture as a gift of God, the holiness of the church relies on the fulfillment of God’s promises, not on the fulfillment of our own purity (Isa 2:1-4). As the Lutheran Confessions reiterate, the church is that assembly of believers among whom the word of God is preached and the sacraments are administered (Augsburg Confession VII). In this way, we are reminded that God’s ways are not our ways. The righteousness of God is to radically show mercy to those who don’t deserve it, and in this, we have hope.