What is important for us to know about the genre of the epistles in the Bible?

from the old testament

• Epistles are not found in the Old Testament.

from the new testament

• Epistles are found exclusively in the New Testament and include Romans, 1 Corinthians, 2 Corinthians, Galatians, Ephesians, Philippians, Colossians, 1 Thessalonians, 2 Thessalonians, 1 Timothy, 2 Timothy, Titus, Philemon, Hebrews, James, 1 Peter, 2 Peter, 1 John, 2 John, 3 John, and Jude. They are known as “occasional letters” because each was written with a specific occasion in mind. Even for larger letters, such as Romans and 1 Corinthians, which may contain many teachings, there is a primary reason for their being written. Thus, the first step in understanding a verse or passage in an epistle is to understand the reason the letter was written.
• Sometimes that is obvious, with the author explicitly stating the reason they are writing. For example, Jude said, “… I found it necessary to write appealing to you to contend for the faith that was once for all delivered to the saints. For certain people have crept in unnoticed who long ago were designated for this condemnation, ungodly people, who pervert the grace of our God into sensuality and deny our only Master and Lord, Jesus Christ” (Jude 3–4).
• At other times, determining the exact reason is more difficult. Romans is an example of that. Given its breadth, some struggle to determine its underlying purpose. Though, from hints throughout it, it seems best to understand the occasion as Paul planning to take the Gospel to Spain (Romans 15:24, 28) and writing to believers he had never met (Romans 1:10–13) to both demonstrate his teaching as well as to appeal for financial support for his planned trip (Romans 15:24). While the letter includes other issues, such as theological differences between the Jewish and Gentile believers (Romans 14:1–3), it’s that missionary-hearted Gospel presentation that undergirds the entire letter.
• Thus, when determining an epistle’s occasion, the goal is to find the main reason (or a couple of reasons) that the author chose to spend the time and great expense to write the letter. An epistle can be thought of like a river. Though it twists and turns, the water flowing through is the same. Likewise, though an epistle might diverge into subtopics or side-ideas, there’s one “stream” flowing through it.
• Examples of occasions include responding to disagreements (1 Corinthians 1:11), expressing thankfulness (Philippians 1:3–5), warning about infiltrators (Jude 3–4), or encouraging persistent obedience in light of surrounding false teachers (1 John 2:26). If a clear purpose is given, it is often stated near the beginning of the letter, but not always (e.g., 1 John 5:13).
• Because these were letters written in the first century, they also tend to follow a predictable pattern common with extra-biblical letters of that time. There’s generally an identification of the sender (Galatians 1:1–2a) and recipient (Galatians 1:2b), a greeting (Galatians 1:3) followed by the body of the letter (Galatians 1:4–6:10), and ending with a closing or salutation (Galatians 6:11–18). One can find hints of the author’s purpose for writing in any of those sections, but knowing they exist helps to identify the actual body of the letter.
• Since the epistles are occasional, not everything in them is directly applicable to us. For example, when Paul tells Timothy to drink a little wine for his stomach (1 Timothy 5:23), he was writing directly to Timothy, not every believer. Additionally, even what applies to us is not always a one-for-one correlation. An example of that is Paul's discussion of the length of men's and women's hair (1 Corinthians 11:2–16). Culturally, certain hairstyles implied someone was a prostitute or otherwise sexually deviant in ways that hair doesn’t always denote today. Paul’s concern was what the hair communicated, not its length specifically. With culturally specific examples like this, we must carefully separate the general principle from the cultural meaning.
• Understanding and applying an epistle requires understanding why the author wrote the letter at all. We are to trace his argument from beginning to end to find out what he meant by a specific verse. Next, we must determine whether what was stated is already a general principle (e.g., Romans 13:8–10) or a culturally specific example from which we need to determine the universal principle. Only once we have the universal principle can we apply an epistle’s teaching to our lives.

implications for today

If we’re not careful, we can easily change a verse’s meaning when read out of context. For epistles, the context can include the entire letter, and it’s important to read the letter before the verse.

This is not a new practice, as we already do this outside the Bible. For example, we don’t jump into the middle of a novel to search for a “favorite quote.” Why, then, do we do that with epistles?

While sometimes it might be laziness where we don’t want to spend the time understanding the author, a large reason we skip an epistle’s context is that well-meaning but questionable bible study practices have encouraged us to read the Bible to see what it means to us. Over time, that search for personal meaning has caused us to lose the author’s meaning. The result is that instead of reading the epistles to hear the argument, we mine it, looking for relatable phrases and ideas.

If you see this issue in your study, combating it is easy! The next time you open an epistle, read it cover-to-cover. Try to follow the author’s arguments and how each section contributes to it. If you are stuck on a passage and do not understand how it connects to the rest of the letter, consult a good commentary. It will help you see the relationship. As you practice reading in context, you will discover yourself applying God's Word faithfully without even trying because you will understand why the author said it instead of just that they said it!