In a well known hadith—found in three of the six canonical Sunni hadith collections (al-Kutub as-Sittah)—it is narrated that Muhammad predicted the Islamic Ummah, "will split into seventy-three sects". This post will quote the variations of this hadith, and shall then touch on a 4th/5th century A.H. book that delves into the hadith, and provides a listing of the 73 sects that the author believes to comprise the said 73 sects, with descriptions of their teachings.
I shall open with two variations/narrations from the Abu/Abi Dawud collection. In the chapter on the Explanation of the Sunnah we read:
4596. It was narrated that Abū Hurairah said: "The Messenger of Allāh said: 'The Jews split into seventy-one or seventy-two sects, and the Christians split into seventy-one or seventy-two sects, and my Ummah will split into seventy-three sects.'"
4597. It was narrated from Abū 'Āmir Al-Hawzanī that Mu'awiyah bin Abī Sufyān stood up among us and said: "The Messenger of Allāh stood up among us and said: 'Those who came before you of the people of the Book split into seventy-two sects, and this Ummah will split into seventy-three sects, seventy-two of which will be in the Fire, and one in Paradise. That is the Jamā'ah (main group of Muslims)." Ibn Yayā and 'Amr added in their Hadīth: "And there will emerge among my Ummah people who will be dominated by those whims and desires as rabies dominates its victim." 'Amr said: "Rabies does not leave any vein or joint of its victim but it enters it." (English Translation of Sunan Abu Dawud, Trans. by, Nasiruddin al-Khattab,Vol.5, pp. 155, 156.) [Alternate online English trans. here]
From the Jami Tirmidhi collection, in the Book on Faith, chapter 18:
(2649) Sayyidina Abu Hurayrah reported that Allah's Messenger said, "The Jews divided into seventy-one sects or seventy-two sects, and the Christians like that. And my ummah will divide into seventy-three sects.
(2650) Sayyidina Abdullahibn Amr reported that Allah's Messenger said, "The same things will be faced by my ummah as the Banu Isra’il faced as a shoe compares with (its pairing) shoe, to the extent that if there was anyone of them to have approached his mother (for sexual intercourse) then there will be in my ummah who would do that. And the Banu Isra’il divided into seventy-two sects and my ummah will divide into seventy-three sects, all of whom will go into the Fire except one millat (sect). “The sahabah (RA) asked (him), “Who are they, O Messenger of Allah (SAW)”. He said, “(Who follow) what I am on and my companions (are on).” (The Translation and the meaning of Jâmi' Tirmidhi, Trans. by Maulana Fazal Ahmad and Rafique Abdur Rehman, Vol. 2, pp. 141, 142.) [Alternate online English trans. here.]
And from the Sunan Ibn Majah collection, in the chapter on the Division of the Nations:
3991. It was narrated from Abu Hurairah that the Messenger of Allāh said: "The Jews split into seventy-one sects and my nation will split into seventy-three sects."
3992. It was narrated from 'Awf bin Mālik that the Messenger of Allāh said: " The Jews split into seventy-one sects, one of which will be in Paradise and seventy in Hell. The Christians split into seventy-two sects, seventy-one of which will be in Hell and one in Paradise. I swear by the One in Whose Hand is the soul of Muhammad, my nation will split into seventy-three sects, one of which will be in Paradise and seventy-two in Hell." It was said: "O Messenger of Allā, who are they?" He said: "The main body."
3993. It was narrated from Anas bin Mālik that the Messenger of Allāh said: "The Children of Israel split into seventy-one sects, and my nation will split into seventy-two, all of which will be in Hell apart from one, which is the main body." (English Translation of Sunan Ibn Mājah, Trans. by, Nasiruddin al-Khattab,Vol.5, pp. 203, 204.) [Alternate online English trans. here.]
And finally, the narrations provided by the late 4th/early 5th century A.H. heresiologist Abu Mansur 'Abd al-Qahir al-Baghdadi, in his al-Farq bayn al-Firaq:
THE tradition has come down to us through the following chain of authorities: abū-Sahl Bishr ibn-Ahmad ibn Bashshār al-Isfarā'ini, ‘Abdāllah ibn-Nājiyah, Wahb ibn Bakiyyah, Khālid ibn-'Abdāllah, Muhammad ibn-'Amr, abū Salmah, abū-Hurairah that the last said, the prophet of Allah—peace be unto him—said: “The Jews are divided into 71 sects, and the Christians are divided into 72 sects, and my people will be divided into 73 sects.” And we are told by abū-Muhammad ‘Abdallāh ibn-Ali ibn Ziyād al-Sumaidhi, who is considered of interest and authoritative, that he heard through the following chain of authorities: Ahmad ibn-al-Hasan ibn-'Abd al-Jabbār, al Haitham ibn-Khārijah, Ismā‘īl ibn-‘Abbās, ‘Abd-al-Rahmān ibn-Ziyād ibn-An'am, ‘Abdallāh ibn-Yazid, ‘Abdallāh ibn ‘Amr, that the prophet of Allah said: “Verily there will happen to my people what happened to the Banū Isrā’īl. The Banū Isrā’īl are divided into 72 religious bodies, and my people will be divided into 73 religious bodies, exceeding them by one. All of them are destined to hell fire except one.” They said: “O, prophet of Allah, which is the one religious body that will escape the fire?” He said: “That to which I belong, and my companions.” The Kādī abū-Muhammad ‘Abdallāh ibn-‘Umar, the Mālikite, says: “We have it from my father, who had it from his father, that Walid ibn-Maslamah said that al-Auzā'i said that we are told by Katādah, who had it from Anas, who had it from the Prophet: ‘Lo, the Banū Isrā’īl are divided into 71 sects, and lo my people will be divided into 72 sects, all of them destined to hell fire except one, and these are the true believers.’ ” (Al-Baghdādī, (Al-Fark Bain al-Firak) Moslem Schisms and Sects, trans. Kate Chambers Seelye, pp. 21, 22.) [Links to online PDF copies of the book HERE.]
The aforementioned al-Baghdadi, in his al-Farq bayn al-Firaq, identifies the 73 sects that he believes constitutes the predicted schisms mentioned in the above narrations. He also adds over a dozen other sects that he feels are too aberrant to be listed under the pale of Islam. In part II of his book he:
...treats of the manner in which this community has been divided into 73. It also contains an explanation of the sects which are collected under the general name of the Millat al-Islām. There are two chapters in this part: one deals with the explanation of the idea underlying the different sects included under the general name of Millat al-Islām; the second concerns the explanation of how the community has become divided, and the enumeration of its 73 sects. (Ibid. pp. 25-39.)
And then in part III he provides an, "explanation of the various opinions of the heretical sects and a detailed explanation of the heresies of each sect." (Ibid. pp. 41-210.)
For those folk who have some interest in the divisions and schisms of the Islamic paradigm, I can think of no better work than al-Baghdadi's to begin one's exploration into the topic.
Grace and peace,