Historical and practical theology

The church's memory

God told his people again and again to remember. In Psalm 78 a singer of Israel resolves to pass on what the fathers handed down:

We will not hide them from their children but will declare to the next generation the praises of the LORD and His might and the wonders He has performed. For He established a testimony in Jacob and appointed a law in Israel, which He commanded our fathers to teach to their children, that the coming generation would know them— even children yet to be born— to arise and tell their own children that they should put their confidence in God, not forgetting His works, but keeping His commandments.

Psalm 78:4-7

The New Testament says the same. Hebrews urges, "Remember your leaders who spoke the word of God to you. Consider the outcome of their way of life and imitate their faith" (Hebrews 13:7). Matthew Henry comments, "The instructions and examples of ministers, who honourably and comfortably closed their testimony, should be particularly remembered by survivors" Matthew Henry. We run our race "surrounded by such a great cloud of witnesses" (Hebrews 12:1).

Historical theology is the study of that memory. It asks not only what the church believed in each age, but why: which question it faced, which texts it read, what it was guarding against. It is not antiquarian curiosity. It is listening to brothers and sisters who read the same Bible before us, often under pressures we have never known.

Growth without change

Again and again the church's confession grew clearer under challenge. When Arius taught in the fourth century that the Son is the highest of creatures, the Council of Nicaea confessed him ‘of one being’ with the Father (Nicaea). When the fifth century argued over how to speak of Christ's deity and humanity, the Council of Chalcedon confessed one person in two natures (Chalcedon). The councils did not invent a new faith. They put into clearer words "the faith entrusted once for all to the saints" (Jude 1:3).

Around 434 Vincent, a monk of the island monastery of Lérins off the coast of southern Gaul, explained this well. Is there progress in the church's faith? Yes, he answered, and great progress, but it must be growth, not change into something else. A child's limbs are small and a grown man's are large, yet he is the same person; so doctrine may be strengthened by the years, enlarged by time and refined with age, while it stays what it was Vincent of Lérins, Commonitory 23.

This study has two dangers. The first is to set tradition beside Scripture, or above it. Jesus rebuked the Pharisees: "You have disregarded the commandment of God to keep the tradition of men" (Mark 7:8). Evangelical faith treasures the church's confessions and tests them, always, by Scripture. The Catholic Church and the Orthodox churches understand Tradition as the apostolic faith handed on in the church's living life, not as human custom; that difference is the subject of The sources of theology.

The second danger is the opposite one: to ignore the church's wisdom, as if no one had read the Bible before us. Those who do so tend to repeat, as something new, mistakes the church long ago answered from Scripture. Historical theology keeps us humble, and lets us read the Bible in company with all who have trusted the same Christ.

Theology for life

Practical theology is where theology becomes the church's life: preaching, worship, pastoral care, teaching and mission. It took shape as a university discipline only in modern times, but the work is as old as the church.

First, preaching. Paul charged Timothy, "Preach the word; be prepared in season and out of season" (2 Timothy 4:2). Henry adds, "Those who love souls must be ever watchful, must venture and bear all the painful effects of their faithfulness, and take all opportunities of making known the pure gospel" Matthew Henry.

Worship is a question for practical theology too: whether the church's prayer and praise, its reading and preaching of the Word, its baptism and Supper, are fitting for the God Scripture reveals. Churches order their worship in many ways, but all can learn from the first believers, of whom Luke says, "They devoted themselves to the apostles’ teaching and to the fellowship, to the breaking of bread and to prayer" (Acts 2:42).

The care of souls has a long tradition of its own. In his Pastoral Rule, Gregory the Great, who became bishop of Rome in 590, called the government of souls "the art of arts". He taught that the same medicine does not suit every illness, and that the pastor must speak one way to the poor and another to the rich, one way to the joyful and another to the sad Gregory the Great, Pastoral Rule. In 1656 Richard Baxter, minister at Kidderminster in England, wrote The Reformed Pastor on Paul's charge, "Keep watch over yourselves and the entire flock" (Acts 20:28). By ‘reformed’ he meant a pastor renewed in earnest, not a party label. The pastor must first watch over his own soul, and then teach his people household by household Richard Baxter, The Reformed Pastor.

Teaching and mission belong here as well. The risen Lord sent his disciples to "make disciples of all nations … teaching them to obey all that I have commanded you" (Matthew 28:19-20). Proclaiming the gospel and teaching people to keep it are one task.

Practical theology's last question is whether theology is lived. James is blunt: "Be doers of the word, and not hearers only. Otherwise, you are deceiving yourselves" (James 1:22). On the call to receive the word, John Wesley notes: "Into your ears, your heart, your life" Wesley. And on the blessing promised a few verses later: "Not barely in hearing, but doing the will of God" Wesley. Paul tells Titus to "speak the things that are consistent with sound doctrine" (Titus 2:1), and then teaches older men and women, the young and slaves how to live. Even of slaves he says that their faithful lives will "adorn the teaching about God our Savior" (Titus 2:10). Sound doctrine shines in the life that fits it.

Four disciplines, one church

Now the four disciplines are together. Biblical theology follows the Bible's story; systematic theology gathers its teaching by subject (Biblical and systematic theology); historical theology listens to the church's memory; practical theology helps all of it become the church's life. The division into four is a modern classroom arrangement. The church's great teachers did all four long before the disciplines had names.

Picture a pastor preparing to preach on John 1. He reads the text closely and in the flow of John's Gospel. He gathers what the whole Bible says about the incarnation, and listens to how the Fathers of Nicaea read these verses. Then he brings it all to the people in front of him, with their griefs and joys. The four are one work, for one church. For why the church matters at all, see Why do we need the church?

Practice