Bu shunday qonunlar ilmiki, ular orqali sanad [rivoyat zanjiri] va matn [hadisning matni] holatini bilish mumkin. Uning maqsadi sahih hadisni boshqalaridan ajratishdir. U ikki turga bo‘linadi: rivoyatga oid hadis ilmi [riwāya] va ma’noga oid hadis ilmi [dirāya]. Rivoyatga oid qismiga Payg‘ambar ﷺ ning so‘zlari, amallari, roziligi va sifatlarini naql qilish kiradi, ularning rivoyat qilinishi, aniqligi va so‘zlarning yozilishi [tahrīr alfādh] bilan bog‘liq holda. Ma’noga oid qismi orqali hadisning haqiqati, shartlari, turlari va rivoyat qoidalari, shuningdek rivoyat qiluvchilarning holati, ularning shartlari, rivoyat turlari va unga aloqador masalalar bilinadi. Dirāya yana hadisda mavjud ma’noning qat’iy matnga zid kelish-kelmasligini bilishni ham o‘z ichiga oladi.

It is the science of those laws whereby the condition of the sanad [chain of transmission] and matn [text of the ḥadīth] is known. Its objective is to differentiate the sahīh hadīth from the others. It is of two types: the science of hadīth pertaining to transmission [riwāya] and the science of the hadīth pertaining to meaning [dirāya]. As for the one pertaining to transmission, it includes the transmission of the sayings of the Prophet , his actions, consent and attributes, with repsect to their narration, accuracy and transcription of words [tahrīr alfādh]. As for the one pertaining to the meaning, the reality, conditions, types and rules of transmission are known through it, as well as the state of the transmitters, their conditions, the types of the transmissions and that which is related to it. Dirāya also covers knowledge of the meaning contained in the hadīth in terms of whether it contradicts a definitive text.