Hadith:

Ḥadith in Islam are the record of the words, actions, and silent approval, traditionally attributed to the Islamic prophet Muhammad ﷺ. Within Islam the authority of hadith as a source for religious law and moral guidance ranks second only to that of the Quran. Quranic verses (such as 24:54, 33:21) enjoin Muslims to emulate Prophet Muhammad ﷺ and obey his judgments, providing scriptural authority for hadith. While the number of verses pertaining to law in the Quran is relatively few, hadiths give direction on everything from details of religious obligations (such as Ghusl or Wudu, Ablutions for Salat prayer), to the correct forms of salutations and the importance of benevolence to slaves. Thus the "great bulk" of the rules of Sharia (Islamic law) are derived from ahadith, rather than the Quran.

Ḥadith is the Arabic word for speech, report, account, narrative. Unlike the Quran. Hadiths were not written down by Prophet Muhammad's ﷺ followers immediately after his death but several generations later when they were collected, collated and compiled into a great corpus of Islamic literature. Different collections of hadith would come to differentiate the different branches of the Islamic faith.

In its classic form a hadith has two parts — the chain of narrators who have transmitted the report (the isnad), and the main text of the report (the matn). Individual hadith are classified by Muslim clerics and jurists into categories such as sahih ("authentic"), hasan ("good") or da'if ("weak"). However, different groups and different scholars may classify a hadith differently.

Among some scholars of Sunni Islam, the term hadith may include not only the supposed words, advice, practices, etc. of Prophet Muhammad ﷺ, but also those of his companions. In Shia Islam, hadith is the embodiment of the Sunnah, the words and actions of the Prophet and his family the Ahl al-Bayt (The Twelve Imams and the Prophet's daughter, Hazrat Fatimah رضی اللہ عنہ).

Classical hadith specialist Ibn Hajar al-Asqalani says that the intended meaning of hadith in religious tradition is something attributed to Prophet Muhammad ﷺ but that is not found in the Quran.

Other associated words possess similar meanings including: khabar (news, information) often refers to reports about Prophet Muhammad ﷺ, but sometimes refers to traditions about his companions and their successors from the following generation; conversely, athar (trace, vestige) usually refers to traditions about the companions and successors, though sometimes connotes traditions about Prophet Muhammad ﷺ.

However, according to the Shia Islam Ahlul Bayt Digital Library Project, "... when there is no clear Qur’anic statement, nor is there a Hadith upon which Muslim schools have agreed. ... Shi’a ... refer to Ahlul-Bayt for deriving the Sunnah of Prophet ﷺ." This means that in Shia Islam the Sunnah draws on the sayings and deeds of the Ahl al-Bayt, i.e. the Imams.

Distinction with Sunnah

The word Sunnah (custom or "all the traditions and practices" of the Islamic prophet ﷺ that "have become models to be followed" by Muslims) is also used in reference to a normative custom of Prophet Muhammad ﷺ or the early Muslim community.

Joseph Schacht describes hadith as providing "the documentation" of the Sunnah.

Another source (Joseph A. Islam) distinguishes between the two sayings:

Whereas the 'Hadith' is an oral communication that is allegedly derived from the Prophet ﷺ or his teachings, the 'Sunna' (quite literally: mode of life, behaviour or example) signifies the prevailing customs of a particular community or people. A 'Sunna' is a practice which has been passed on by a community from generation to generation en masse, whereas the Ahadith are reports collected by later compilers often centuries removed from the source. A practice which is contained within the Hadith may well be regarded as Sunna, but it is not necessary that a Sunna would have a supporting hadith sanctioning it.

Some sources (Khaled Abou El Fadl) limit hadith to verbal reports, with the deeds of Prophet Muhammad ﷺ and reports about his companions being part of the Sunnah, but not hadith.

Hadith and Quran:

The theological importance of hadith comes from several verses in the Quran such as:

Say: Obey Allah and obey the Messenger, but if you turn away, he (the Prophet) is only responsible for the duty placed on him (i.e. to convey Allah’s Message) and you for that placed on you. If you obey him, you shall be on the right guidance. The Messenger’s duty is only to convey (the message) in a clear way. (An-Nur 24:54)

In God's messenger you have indeed a good example for everyone who looks forward with hope to God and the Last Day, and remembers God unceasingly. (Al-Ahzab 33: 21)

The hadith literature is based on spoken reports in circulation after the death of Prophet Muhammad ﷺ. Unlike the Quran, hadiths were not promptly written down during Prophet Muhammad's ﷺ life or immediately after his death. Hadith were evaluated and gathered into large collections during the 8th and 9th centuries, generations after the death of Prophet Muhammad ﷺ, after the end of the era of the "rightful" Rashidun Caliphate, over 1,000 km (620 mi) from where Prophet Muhammad ﷺ lived. "Many thousands of times" more numerous than Quranic verse, ahadith have been described as resembling layers surrounding the “core” of the Islamic belief (the Quran). Well-known, widely accepted Hadiths make up the narrow inner layer, with ahadith becoming less reliable and accepted with each layer stretching outward.

Unlike the Quran, hadiths are “grounded in the prosaic moments of everyday life". The reports of behavior to be emulated that were collected include details of ritual religious practice such as the five salat (obligatory Islamic prayers) that are not found in the Quran, but also everyday behavior such as table manners, dress, posture. Hadith are also regarded by Muslims as important tools for understanding things mentioned in the Quran but not explained, a source for tafsir (commentaries written on the Quran).

Some important elements, which are today taken to be a long-held part of Islamic practice and belief are not mentioned in the Quran at all, but are derived solely from the hadith.

Comparative importance of hadith:

It has been narrated through a chain of narrators, including Prophet Muhammad ﷺ ibn Isma'il and originating with Imam Ja'far al-Sadiq, that the Prophet Muhammad ﷺ once addressed his people in Mina saying ‘O people, whatever comes to you in the form of my Hadith, if it agrees with the Holy Book of Allah, it is genuine, but whatever comes to you that does not agree with the book of Allah you must know that I have not said it.'

Components, schools, types:Impact:

The hadith had a profound and controversial influence on tafsir (commentaries of the Quran). The earliest commentary of the Quran known as Tafsir Ibn Abbas is sometimes attributed to the companion Hazrat Ibn Abbas رضي الله عنه.

The hadith were used in forming the basis of Sharia (the religious law system forming part of the Islamic tradition), and fiqh (Islamic jurisprudence). The hadith are at the root of why there is no single fiqh system, but rather a collection of parallel systems within Islam. Much of early Islamic history available today is also based on the hadith

Types:

Hadith may be hadith Qudsi (sacred hadith) which some Muslims regard as the words of Allah or hadith Sharif (noble hadith) which are Prophet Muhammad's ﷺ own utterances.

According to as-Sayyid ash-Sharif al-Jurjani, the hadith Qudsi differ from the Quran in that the former are "expressed in Prophet Muhammad's ﷺ words", whereas the latter are the "direct words of Allah".

An example of a hadith Qudsi is the hadith of Hazrat Abu Hurairah who said that Prophet Muhammad ﷺ said:

When God decreed the Creation He pledged Himself by writing in His book which is laid down with Him: My mercy prevails over My wrath.

In the Shia school of thought, there are two fundamental viewpoints of hadith: The Akhbari view and the Usuli view. The Usuli scholars stress the importance of scientific examination of hadiths using ijtihad while the Akhbari scholars take all hadiths from the four Shia books as authentic.

Components:

Different branches of Islam refer to different collections of hadith, though the same incident may be found in hadith in different collections:

In the Sunni branch of Islam, the canonical hadith collections are the six books, of which Sahih al-Bukhari and Sahih Muslim generally have the highest status. The other books of hadith are Sunan Abu Dawood, Jami` at-Tirmidhi, Al-Sunan al-Sughra and Sunan ibn Majah. However the Malikis, one of the four Sunni "schools of thought" (madhhabs), traditionally reject Sunan ibn Majah and assert the canonical status of Muwatta Imam Malik

In the Twelver Shi'a branch of Islam, the canonical hadith collections are the Four Books: Kitab al-Kafi, Man la yahduruhu al-Faqih, Tahdhib al-Ahkam, and Al-Istibsar.

In the Ibadi branch of Islam, the main canonical collection is the Tartib al-Musnad. This is an expansion of the earlier Jami Sahih collection, which retains canonical status in its own right.

The Ismaili shia sects use the Daim al-Islam as hadith collections.

The Ahmadiyya sect generally rely on the Sunni canons.

Some minor groups, collectively known as Quranists, reject the authority of the hadith collections altogether.

In general, the difference between Shi'a and Sunni collections is that Shia give preference to hadiths credited to the Prophet's family and close associates (Ahl al-Bayt), while Sunnis do not consider family lineage in evaluating hadith and Sunnah narrated by any of twelve thousand companions of Prophet Muhammad ﷺ.