Apabila masa berlalu, semakin ramai perawi terlibat dalam setiap isnad, dan keadaan itu menuntut disiplin yang ketat dalam penerimaan hadis; kaedah yang mengatur disiplin ini dikenali sebagai Mustalah al-Hadith (Pengelasan Hadis).

As time passed, more reporters were involved in each isnad, and so the situation demanded strict discipline in the acceptance of ahadith; the rules regulating this discipline are known as Mustalah al-Hadith (the Classification of Hadith).

Di kalangan ahli hadis terdahulu (muhaddithin, ulama hadis), kaedah dan kriteria yang mengawal kajian mereka terhadap hadis adalah sangat teliti, namun sebahagian istilah mereka berbeza dari seorang ke seorang, dan prinsip-prinsip mereka mula dicatat secara sistematik, tetapi bertebaran dalam pelbagai kitab, contohnya dalam Al-Risalah karya al-Shafi'i (w. 204H), Pendahuluan kepada Sahih Muslim (w. 261H) dan al-Jami' karya al-Tirmidhi (w. 279H); banyak kriteria ahli hadis terdahulu, contohnya al-Bukhari, telah disimpulkan oleh ulama kemudian melalui kajian yang teliti terhadap perawi-perawi atau sanad-sanad yang diterima dan ditolak oleh mereka.

Amongst the early traditionists (muhaddithin, scholars of Hadith), the rules and criteria governing their study of Hadith were meticulous but some of their terminology varied from person to person, and their principles began to be systematically written down, but scattered amongst various books, e.g. in Al-Risalah of al- Shafi'i (d. 204), the Introduction to the Sahih of Muslim (d. 261) and the Jami' of al-Tirmidhi (d. 279); many of the criteria of early traditionists, e.g. al-Bukhari, were deduced by later scholars from a careful study of which reporters or isnads were accepted and rejected by them.

Salah satu karya terawal yang cuba meliputi Mustalah secara menyeluruh, dengan menggunakan istilah yang diterima umum, ialah karya al-Ramahurmuzi (w. 360). Sumbangan besar seterusnya ialah Ma'rifah 'Ulum al-Hadith oleh al-Hakim (w. 405), yang meliputi lima puluh klasifikasi hadis, tetapi masih meninggalkan beberapa perkara yang tidak disentuh; Abu Nu'aim al-Isbahani (w. 430) melengkapkan sebahagian bahagian yang tertinggal dalam karya ini. Selepas itu muncul Al-Kifayah fi 'Ilm al-Riwayah karya al-Khatib al-Baghdadi (w. 463) dan sebuah lagi karya mengenai cara mengajar dan mempelajari hadis; sarjana-sarjana kemudian dianggap sangat terhutang budi kepada karya al-Khatib.

One of the earliest writings to attempt to cover Mustalah comprehensively, using standard (i.e. generally-accepted) terminology, was the work by al-Ramahurmuzi (d. 360). The next major contribution was Ma'rifah 'Ulum al-Hadith by al- Hakim (d. 405), which covered fifty classifications of Hadith, but still left some points untouched; Abu Nu'aim al-Isbahani (d. 430) completed some of the missing parts to this work. After that came Al-Kifayah fi 'Ilm al- Riwayah of al-Khatib al-Baghdadi (d. 463) and another work on the manner of teaching and studying Hadith; later scholars were considered to be greatly indebted to al-Khatib's work.

Selepas sumbangan lanjut oleh Qadi 'Iyad al-Yahsubi (w. 544) dan Abu Hafs al-Mayanji (w. 580) antara lain, lahirlah karya yang, walaupun kecil saiznya, begitu menyeluruh dalam penghuraiannya yang cemerlang tentang subjek ini sehingga ia menjadi rujukan standard bagi beribu-ribu ulama dan penuntut ilmu Hadith pada berkurun-kurun yang akan datang hingga ke hari ini: 'Ulum al-Hadith karya Abu 'Amr 'Uthman Ibn al-Salah (w. 643), yang lazimnya dikenali sebagai Muqaddimah Ibn al-Salah, disusun semasa beliau mengajar di Dar al-Hadith di beberapa bandar di Syria. Antara banyak karya llain yang kemudian dibina berdasarkan karya Ibn al-Salah ialah:

After further contributions by Qadi 'Iyad al- Yahsubi (d. 544) and Abu Hafs al-Mayanji (d. 580) among others, came the work which, although modest in size, was so comprehensive in its excellent treatment of the subject that it came to be the standard reference for thousands of scholars and students of Hadith to come, over many centuries until the present day: 'Ulum al- Hadith of Abu 'Amr 'Uthman Ibn al-Salah (d. 643), commonly known as Muqaddimah Ibn al-Salah, compiled while he taught in the Dar al-Hadith of several cities in Syria. Some of the numerous later works based on that of Ibn al-Salah are:

• Ringkasan Muqaddimah, Al-Irshad karya al-Nawawi (w. 676), yang kemudian beliau ringkaskan lagi dalam Taqrib; al-Suyuti (w. 911) menyusun sebuah syarah yang berharga terhadap yang terakhir ini, berjudul Tadrib al-Rawi.

• An abridgement of Muqaddimah, Al-Irshad by al- Nawawi (d. 676), which he later summarised in his Taqrib; al-Suyuti (d. 911) compiled a valuable commentary on the latter entitled Tadrib al-Rawi.

• Ikhtisar 'Ulum al-Hadith karya Ibn Kathir (w. 774 H), Al-Khulasah karya al-Tibi (w. 743 H), Al-Minhal karya Badr al-Din b. Jama'ah (w. 733 H), Al-Muqni' karya Ibn al-Mulaqqin (w. 802 H) dan Mahasin al-Istilah karya al-Balqini (w. 805 H), kesemuanya merupakan ringkasan bagi Muqaddimah Ibn al-Salah.

• Ikhtisar 'Ulum al-Hadith of Ibn Kathir (d. 774), Al-Khulasah of al-Tibi (d. 743), Al- Minhal of Badr al-Din b. Jama'ah (d. 733), Al- Muqni' of Ibn al-Mulaqqin (d. 802) and Mahasin al-Istilah of al-Balqini (d. 805), all of which are abridgements of Muqaddimah Ibn al- Salah.

• Al-Nukat karya al-Zarkashi (w. 794), Al-Taqyid wa 'l-Idah karya al-'Iraqi (w. 806) dan Al-Nukat karya Ibn Hajar al-'Asqalani (w. 852), kesemuanya merupakan catatan tambahan terhadap perkara-perkara yang dikemukakan oleh Ibn al-Salah.

• Al-Nukat of al-Zarkashi (d. 794), Al-Taqyid wa 'l-Idah of al-'Iraqi (d. 806) and Al-Nukat of Ibn Hajar al-'Asqalani (d. 852), all of which are further notes on the points made by Ibn al- Salah.

• Alfiyyah al-Hadith karya al-'Iraqi, sebuah penulisan semula Muqaddimah dalam bentuk puisi panjang, yang menjadi subjek beberapa syarahan, termasuk dua (satu panjang, satu pendek) oleh pengarangnya sendiri, Fath al-Mughith karya al-Sakhawi (m. 903), Qatar al-Durar karya al-Suyuti dan Fath al-Baqi karya Shaykh Zakariyyah al-Ansari (m. 928).

• Alfiyyah al-Hadith of al-'Iraqi, a rewriting of Muqaddimah in the form of a lengthy poem, which became the subject of several commentaries, including two (one long, one short) by the author himself, Fath al-Mughith of al-Sakhawi (d. 903), Qatar al-Durar of al- Suyuti and Fath al-Baqi of Shaykh Zakariyyah al-Ansari (d. 928).

• Al-Iqtirah karya Ibn Daqiq al-'Id (w. 702). Tanqih al-Anzar karya Muhammad b. Ibrahim al-Wazir (w. 840), yang menjadi subjek syarah oleh al-Amir al-San'ani (w. 1182).

• Al-Iqtirah of Ibn Daqiq al-'Id (d. 702). Tanqih al-Anzar of Muhammad b. Ibrahim al- Wazir (d. 840), the subject of a commentary by al-Amir al-San'ani (d. 1182).

• Nukhbah al-Fikr karya Ibn Hajar al-'Asqalani, yang kembali menjadi subjek beberapa syarah, termasuk syarah oleh pengarangnya sendiri, syarah oleh anaknya Muhammad, serta syarah-syarah oleh 'Ali al-Qari (w. 1014), 'Abd al-Ra'uf al-Munawi (w. 1031) dan Muhammad b. 'Abd al-Hadi al-Sindi (w. 1138). Di antara mereka yang menyusun ulang Nukhbah dalam bentuk syair adalah al-Tufi (w. 893) dan al-Amir al-San'ani.

• Nukhbah al-Fikr of Ibn Hajar al-'Asqalani, again the subject of several commentaries, including one by the author himself, one by his son Muhammad, and those of 'Ali al-Qari (d. 1014), 'Abd al-Ra'uf al-Munawi (d. 1031) and Muhammad b. 'Abd al-Hadi al-Sindi (d. 1138). Among those who rephrased the Nukhbah in poetic form are al-Tufi (d. 893) and al- Amir al-San'ani.

• Alfiyyah al-Hadith karya al-Suyuti, karya berbentuk syair yang paling komprehensif dalam bidang ini. Al-Manzumah karya al-Baiquni, yang diperluas oleh, antara lain, al-Zurqani (w. 1122) dan Nawab Siddiq Hasan Khan (w. 1307). Qawa'id al-Tahdith karya Jamal al-Din al-Qasimi (w. 1332).

• Alfiyyah al-Hadith of al-Suyuti, the most comprehensive poetic work in the field. Al-Manzumah of al-Baiquni, which was expanded upon by, amongst others, al-Zurqani (d. 1122) and Nawab Siddiq Hasan Khan (d. 1307). Qawa'id al-Tahdith of Jamal al-Din al-Qasimi (d. 1332).

Taujih al-Nazar karya Tahir al-Jaza'iri (w. 1338), ringkasan kitab Ma'rifah karya al-Hakim.

• Taujih al-Nazar of Tahir al-Jaza'iri (d. 1338), a summary of al-Hakim's Ma'rifah.