What is the text of the Prophet's (peace be upon him) hadith which states that "at the turn of every century, someone will be sent to renew the affairs of this nation's religion"? And who are the scholars who are considered renewers of the nation throughout history, and who is the last of them?

The Hadith, "Indeed, Allah will send to this nation at the head of every hundred years one who will renew its religion for it," is authentic by the consensus of the Huffaz (Hadith masters). The renewer (mujaddid) has conditions, among them that he be alive at the end of the century, known for knowledge, a propagator of the Sunnah, encompassing various branches of knowledge, and that his knowledge reach the people of his time, and that he be from the Prophet's household, and an individual mujtahid (one who exercises independent reasoning).

However, it is not a condition that he encompass all branches of knowledge, or be from the Prophet's household, or be a single individual. Rather, it includes everyone who benefits the Ummah and renews something of its religious affairs for it. And the renewal may be in different fields, such as courage, fiqh (jurisprudence), Hadith, asceticism, or enjoining good and forbidding evil. It is not necessary for all qualities to be gathered in one person; the renewers may be dispersed.

Examples of renewers include: Umar ibn Abd al-Aziz in the first century, Ash-Shafi'i in the second, as well as scholars in subsequent centuries, such as Muhammad al-Amin ash-Shinqiti, Al-Albani, Ibn Baz, and Al-Uthaymin.