It is also authentically reported in the Sunan collections from Safīnah, the freedman of the Prophet—may Allah bless him and grant him peace—that the Prophet—may Allah bless him and grant him peace—said: “After me, the caliphate will last thirty years; then it will become monarchy.” (1).
Umar ibn Abd al-Azīz—may Allah have mercy on him—whom the Muslims recognized as a rightly guided caliph, used to say: “The Messenger of Allah—may Allah bless him and grant him peace—and those vested with authority after him established practices. Following them constitutes affirmation of the Book of Allah, completes obedience to Allah, and strengthens adherence to Allah’s religion. No one has the right to alter or replace them, nor may any heed be paid to the opinion of anyone who opposes them. Whoever is guided by them is rightly guided; whoever seeks victory through them will be granted victory; and whoever opposes them and follows a path other than that of the believers, Allah will leave him to what he has chosen and make him burn in Hell—what an evil destination!” (2).
These three foundations—the Book of Allah, the Sunnah of His Messenger, and the path of His believing servants—