What are Hadith?

Secondary (or Supplemental) Books

by James S. Coates

The Primary Principle

Perhaps the most important thing to understand about hadith is that the Qur’an is more authoritative. If there is not a direct Qur’anic reference to cross-reference and unequivocally confirm a hadith, then the hadith holds less authority. This principle underlies everything that follows.

Hadith in Context

Similar to Judaism which has a core book (the Torah) and secondary oral traditions (the Talmud), Islam has a core book (the Qur’an) and a recorded “oral tradition” that we call “al-Hadith.” The Talmud and Hadith have both been recorded in many hundreds of volumes and both serve to supplement understanding of their respective core books (Torah and Qur’an) and build upon the foundation of religious practice.

The hadith are the “secondary source” after the Qur’an to which Muslims refer in order to supplement their faith, interpret Islamic Shari’ah, or to form opinions on interpretation of our religion.

How Hadith Were Recorded

Hadith writing began very early. Many of the Sahaba (Companions of the Prophet) and their students recorded hadith in suhuf (personal written notes), and these early texts circulated among the Tabi’een (the generation after the Companions) long before the major compilations.

However, the canonical collections—the large, systematically verified works we largely rely on today—were compiled and codified later:

Imam Malik’s Muwatta (c. 760s CE, approximately 140 years after the Prophet)
Sahih al-Bukhari (d. 870 CE) and Sahih Muslim (d. 875 CE), approximately 240 years after the Prophet
Other collections (Abu Dawud, Tirmidhi, Nasa’i, Ibn Majah) followed in the same 9th century

So while hadith recording itself began very early, the formal canonisation of those reports into comprehensive, systematically authenticated books came in the 8th–9th centuries. Both points fit within the same historical development.

We call the chain of transmission ‘isnad‘ (chain of narration), and this tells us whether the people who narrated the hadith are considered trustworthy or not. Isnad does not tell us that what was recorded in the hadith is definitively what was said or happened. Hadith are basically hearsay evidence and have many classifications of authenticity of isnad, not accuracy of content. This is why the hadith are a secondary source that supplement the Qur’an.

Keep in mind that although Muslims believe in the Bible (New Testament), we don’t rely on it for our belief system partly for the reason that the New Testament was composed over a century after Jesus and compiled into its current form over several more centuries, without an isnad system to authenticate transmission. The Prophet never saw our books of hadith and Jesus never saw the Bible to authorise their authenticity.

The Nature of Hadith

Unlike the Qur’an, the hadith were transmitted by a chain of ordinary individuals about the things the Prophet Muhammad reportedly said (qawl), did (fi’l), or approved (taqrir). The Prophet Muhammad never authorised or saw these compilations or recordings. They were not preserved with the same integrity as the Qur’an. The hadith have errors, contradictions, and are NOT considered “infallible.” The Qur’an is the primary authoritative source of all things in Islam. The hadith are secondary—they supplement or clarify the Qur’an and are subordinate to it.

Classifications of Hadith

Hadith are categorised based on what we call isnad, or trustworthiness of the chain of narrators. The three categorisations are:

Sahih (Strong) – Narrators were known to be reputable.

Hasan (Good) – Narrators may be questionable.

Da’if (Weak) – Serious problems with narrators or method of transmission.

It is important to note that a “Strong” narration may still have inaccuracies or have different narrations of the same event described in Islamic history. The categorisation only speaks to the reputations of the individuals in the chain over generations or the method of transmission: were the individuals transmitting known to be liars, cheats, abusers, or trustworthy people?

Also, as we know, even a story told by the most trustworthy people in a chain of many individuals can come out on the other side of the chain a very different story than when it began.

The Science of Hadith

In order to sort these matters out, we have to study the event in-depth according to hundreds of other hadith, Qur’an, and Islamic history to determine the outcome. There is no room for “clever slogans,” rash interpretations, or assumptions that many deviant Muslims or anti-Islam proponents try to assert. It is why we call the study of hadith “The Science of Hadith.” It takes serious long-term study, and every hadith that remotely can speak to a situation must be evaluated in light of each other.

Divisions among Muslims have arisen over the existence of volumes of hadith, interpretations of hadith, and even ascribed authors or recorders of hadith. Entire schools of thought have been formed and draw on some hadith more than others. The Sunni and Shi’a historical divide has been greatly amplified over the existence and interpretations of hadith.

How Hadith Function: An Example

An example of hadith that would hold a great degree of authority in a valid interpretation of Islam can be seen in the Qur’anic verse that tells Muslims to establish formal prayers. The Qur’an does not tell us how to do that:

“Verily, I am Allah: There is no god but I: So serve thou Me (only), and establish regular prayer for celebrating My praise.” (Qur’an 20:14)

So, we have to refer to hadith that directly describe the topic in order to learn how. The Qur’an makes the mandate; the hadith explain the mandate.