Expository preaching may be defined as that which seeks to explain and apply a unit of Scripture, such that the main point of that unit of Scripture becomes the main point of the sermon.

Can a case for expository preaching be made from the Bible itself?

James F. Stitzinger thinks so.  He reasons as follows.

Preaching in the Bible is both revelatory (declaring new truths) and explanatory (explaining and applying known truths).

Old Testament

Old Testament examples include

• Moses (Deut 31-33)
• Joshua (Josh 23:2-16; 24:2-27)
• David (Psalms 8, 9, 16, 22, 24, 34, 68, 75, 89, 93, 105, 110, 119, 136, 145 reveal the nature and character of God, whereas Psalms 1, 23, 32, 37, 40, 46, 50, 66, 78, 92, 100, 104, 106, 118, 128, 150 – see esp. Psa 32:8 – are more explanatory).
• Solomon (see especially Prov 1:2-3; 2 Chr 6:1-42; Eccl 1:12-13; 12:9-10)
• and, of course, the prophets, whose messages mixed ‘foretelling’ (revelatory preaching, as in Isaiah 9, 53), with ‘forthtelling’ (explaining and applying what was already known about God to contemporary issues, as in Isa 1:2-31; Isa 6).

Explanatory preaching is prominent in

• Josiah’s command to repair and reform the house of the Lord (2 Kings 22-23);
• Ezra’s study and teaching of the law (Ezra 7:10);
• Nehemiah’s comments about the law (Neh 8:1-8);
• Daniel’s explanation of his vision of seventy weeks (Daniel 9).
• Samuel (1 Sam 12:23), Isaiah (Isa 30:9), Jeremiah (Jer 32:33), and Malachi (Mal 2:9) all spoke of the work as explanation.

It is clear from all this (Stitzinger writes) that even as the words and works of God were unfolding there was a need to explain and apply them to the people.  In other words, there was a need for expository preaching.

New Testament

Turning to the New Testament, we meet Jesus himself, who came preaching (Mark 1:14) and teaching (Matt 9:35).  From an early age, he demonstrated profound knowledge and understanding of Scripture (Lk 2:46-50).  His preaching included both revelation and explanation (see, for example, Matthew 5-7; Luke 4:16-30).

We may say of Jesus’ preaching that

• He spoke with authority (Matt 7:29);
• He made careful use of other Scriptures in his explanations;
• He lived out what he taught;
• He taught simply to adapt to the common man (Mark 12:37);
• His teaching was often controversial (Matt 10:35-37).

As a result, while some were confounded (Lk 4:28), others rejoiced (Mt 15:15).

The preaching of the leaders of the early church included both revelatory and explanatory elements (Peter, Acts 2:14-36; Stephen, Acts 7:2-53; Paul, Acts 17:16-31; James, Acts 15:14-21).

William Barclay remarks that even the letters of Paul are

‘sermons far more than they are theological treatises. It is with immediate situations that they deal. They are sermons even in the sense that they were spoken rather than written. They were not carefully written out by someone sitting at a desk; they were poured out by someone striding up and down a room as he dictated, seeing all the time in his mind’s eye the people to whom they were to be sent. Their torrential style, their cataract of thought, their involved sentences all bear the mark of the spoken rather than of the written word.’

In fact, Paul devoted his life to preaching Christ (1 Cor 1:23; 2:2; 2 Cor 4:5).  Again, there are elements of revelation (Rom 1:18; 1 Cor 2:10; Eph 3:5) and explanation (Rom 15:4; 1 Cor 10:11, 17; 1 Thess 4:1; 2 Thess
3:14; 1 Tim 1:5).

When Paul instructed Timothy to ‘preach the Word’ (2 Tim 4:2), to ‘teach and preach these principles’ (1 Tim 6:2), and to ‘instruct’ others (1 Tim 6:17) he was being encouraged in a ministry of explanation, rather than of revelation.  Timothy, and others like him, were to explain and apply truths that had already been revealed.  They were to expound God’s truth to people who needed to be grounded and established in their faith (1 Tim 4:13; 2 Tim 2:15; 4:2-5).

According to Hebrews 1:1-3 God’s revelation has climaxed and been completed in Christ.  The task of the preacher, then, is to faithfully explain and apply the message that has already been revealed.

Note

I think that the above makes a convincing case for preaching and teaching the Bible.  I’m not sure that it makes quite such a strong case for expository preaching as it is usually understood in evangelical circles.