And al-Haafidh said in Fathul-Baaree in explanation of the head of the century, "Meaning: at the end of the century."

"The author of Majaalisul-Abraar said, ‘And what is meant by revival of that which has been effaced from action upon the Book and the Sunnah and command according to them,’ and he said in it, ‘And that reviver (mujaddid) will not be known except by preponderance of opinion of those scholars who live in his time – due to his condition and the benefit that is derived from his knowledge – since the reviver (mujaddid) must be one having knowledge of the branches of knowledge of the Religion, that which is apparent and that which is not apparent, aiding the Sunnah (naasirun lis-Sunnah), cutting off innovation, and that his knowledge is recognised by the people of his time …"

So it is clear that the mujaddid will not be except one who is a scholar of the branches of knowledge of the Religion and along with that strives and gives great attention day and night to reviving matters of the Sunnah and spreading it, and aiding its companion, and killing-off innovation and new matters and effacing them and routing its people with the tongue, or by writing books, or teaching, or so on – and one who is not like that can in no way be a mujaddid – even if he is a scholar of Religious sciences, famous amongst the people and referred to by them …"

"Further Note: And know that it is not essential that at the head of each century there should only be a single reviver, rather it is possible for there to be more than one. Al-Haafidh Ibn Hajr said in Tawaaliyut-Ta‘sees, ‘Some scholars have taken this hadeeth to refer to more than a single person, and it is possible from the wording of the hadeeth which we have quoted … since the hadeeth indicates that the revival indicated is general for all the people of that time. And this was very possible with regard to ’Umar ibn ’Abdul-’Azeez and then ash-Shaafi’ee. But as for those who came after that, then they had others to share with them."