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An Initial Introduction to Theology & Religion Resources: Primary/Secondary Sources

Introductory guide to theological methods and resources.

The Didache

Treatise from late first century or early 2nd century


First line: "Teaching of the Lord to the Gentiles (or Nations) by the Twelve Apostles"


Oldest surviving written catechism;



Christian ethics

Rituals such as baptism and Eucharist

Church organization


Church Fathers: Some considered it as part of the New Testament; others rejected it as non-canonical.

Types of Sources

Defining Primary and Secondary Sources

Libraries and archives hold objects, like documents and books, which help us  find out what happened in the past. One way to organize these objects is to divide them into primary and secondary sources. What makes an object a primary source or a secondary source often depends on how you use it.

Primary and secondary sources, when used together, help us to understand people, ideas and events from the past.

Primary Sources

Image of professor

People use original, first-hand accounts as building blocks to create stories from the past. These accounts are called primary sources, because they are the first evidence of something happening, or being thought or said.

Primary sources are created at the time of an event, or very soon after something has happened. These sources are often rare or one-of-a-kind. However, some primary sources can also exist in many copies, if they were popular and widely available at the time that they were created.

All of the following can be primary sources:

  • Diaries
  • Letters
  • Photographs
  • Art
  • Maps
  • Video and film
  • Sound recordings
  • Interviews
  • Newspapers
  • Magazines
  • Published first-hand accounts, or stories

Secondary Sources

Second-hand, published accounts are called secondary sources. They are called secondary sources because they are created after primary sources and they often use or talk about primary sources. Secondary sources can give additional opinions (sometimes called bias) on a past event or on a primary source. Secondary sources often have many copies, found in libraries, schools or homes.

All of the following can be secondary sources, if they tell of an event that happened a while ago:

  • History textbooks
  • Biographies
  • Published stories
  • Movies of historical events
  • Art
  • Music recordings

When Is a Primary Source Not a Primary Source?

You may have noticed that some things are on both the lists of primary and secondary sources. This isn't a mistake. The difference between a primary and secondary source is often determined by how they were originally created and how you use them.

Here's an example: a painting or a photograph is often considered a primary source, because paintings and photographs can illustrate past events as they happened and people as they were at a particular time. However, not all artworks and photographs are considered primary sources. Read on!

C.W. Jefferys was a talented artist who painted many scenes from Canada's past. His paintings and drawings show the War of 1812, the Rebellions of 1837-38 and many of Canada's explorers from the 1600s and 1700s. But C.W. Jefferys lived from 1869-1951, so he never saw the subjects of these paintings! Instead, he did a lot of research using primary sources to create his illustrations. Some people would argue that his illustrations are not primary sources. Although they illustrate past events, they were created long after the events they show, and they tell you more about C.W. Jefferys' own ideas and research.

Other people would argue that C.W. Jefferys' paintings and drawings are primary sources. They would say that his perspective, his bias, and the way he illustrated historical events are reflections of what he thought and what he believed. If you use C.W. Jefferys' paintings to talk about him, or the world he lived in, then they can also be primary sources.

What do you think? How would you organize paintings created long after an event happened? Are they primary or secondary sources? Why?

And Now the Most Important Question: Who Cares?

What's the big deal over primary and secondary sources anyway? Why should you care, especially if adults can't even make up their minds which is which?

A German historian, over 100 years ago, said it was important to write about the past, "as it really happened." Most people today agree that it is impossible to know what exactly happened in history. (Most people can't remember exactly what happened last week, let alone a long time ago!) However, if we aren't careful about the facts, we can really make a mess and even create some big lies about the past.

Think of it like playing the telephone game. That's the game where you whisper something in a friend's ear that they have to repeat to another friend, and so on. It works for the first little while, but the chance of someone getting it wrong increases with the number of people who repeat it. Going back to primary sources is like going back to the first person in the telephone game.

Doing research is all about trust. If you trust the person who created a secondary source, then there isn't a problem about using it. However, if you don't trust that person, if you think their version is a exaggerated or biased, or if you want to see the original evidence for yourself, then you have to go to the primary sources.

Checklist: primary and secondary sources: Can you tell the difference using these questions?

  • created at the time of an event, or very soon after
  • created after event; sometimes a long time after something happened
  • created by someone who saw or heard an event themselves
  • often uses primary sources as examples
  • often one-of-a-kind, or rare
  • expresses an opinion or an argument about a past event
  • letters, diaries, photos and newspapers (can all be primary sources)
  • history text books, historical movies and biographies (can all be secondary sources)

Questioning Primary Sources

Knowing the differences between primary and secondary sources is the first step to better understanding the past. Once you have found your primary sources, it is important to question them to find out what they say and who made them.

A primary source is created every time you send an email, take a photograph, or write in your journal. These primary sources reflect the worries, concern, or opinions you have when you create them.

As you know, these documents can express feelings of love, joy, unhappiness or dislike. Sometimes the emotions of the creator or author can be clearly seen in primary sources. Other times, they are hidden. Sometimes a primary source will contain lies or mistaken information. Sometimes a primary source is actually a fake, made to look old and important.

When looking at primary sources, there are several questions you should always ask to help you understand the material. These questions will also help you figure out if a source is authentic or fake. Authentic primary sources are great research material for projects, but you need to be careful of fake ones!

Sometimes it will be easy to get the answers to your questions, and sometimes it will be impossible. Don't worry if it gets difficult -- just asking the questions is important.

The five key questions:

What is the primary source? Is it a photo? If so, is it in black and white or colour? Is it a letter? If so, is it typed, or handwritten?
Who wrote the letter, took the photo or painted the painting? Can you be sure it was really that person who made it?
When was the primary source created? How can you tell its age?
Can you tell where the primary source was created?
Why was the primary source created? Does it tell a story? Is it a love letter? Is it an order from an officer to a soldier? Is it a picture of the Rocky Mountains? Does the primary source tell you why it was created? Can you guess why it was created?

When you are studying a primary source, write down your answers to the five key questions. Do you think that the primary source is authentic? Do you think it is fake? An authentic source can tell you lots about the people, places, and events of the past. What did people think in the past? How did they talk to each other? What did they wear? You can find out for yourself using primary sources.

A faked source can also tell you a lot. Why would someone go to all of that trouble to fool us? What were they hiding and what did they want us to think? Being a historian is a lot like being a detective, with primary sources as the evidence. It's your job to find out what really happened! Remember that history is never final. Accounts of the past are as different as the people who create them. That means there is lots of room for you to research and write your own story.

Tertiary Sources


In research, the term tertiary source is a relative term. What is considered tertiary depends on what is considered primary and secondary. A tertiary source may thus be understood as a selection, distillation, summary or compilation of primary sources, secondary sources, or both the distinction between primary source and secondary source is standard in historiography, while the distinction between these sources and tertiary sources is more peripheral, and is more relevant to the scholarly research work than to the published content itself.

In some contexts typical instances of tertiary sources are bibliographies, library catalogs, directories, reading lists and survey articles.  Encyclopedias and textbooks are examples of written materials that typically embrace both secondary and tertiary sources, presenting on the one hand commentary and analysis, while on the other attempting to provide a synoptic overview of the material available on the topic.

The classification of a given source is subjective and contextual. For example, a modern encyclopedia might be generally considered a tertiary source, but an ancient encyclopedia is generally considered a primary source. The difference is because the modern encyclopedia is used as a source for information about a topic, and the ancient encyclopedia is understood as a source of information about the state of knowledge in the time period when the encyclopedia was written. However, even a modern encyclopedia is a primary source for some facts, such as the name of its publisher.