the righteous servant said:

‘And I was a witness over them as long as I remained among them.’”

(Sūrat al-Mā’idah: 117) (1).

Allah Most High also says:

“Muhammad is only a messenger. Messengers have passed away before him. So if he dies or is killed, will you turn back on your heels? Whoever turns back on his heels will not harm Allah in the least, and Allah will reward the grateful.”

(Sūrat Āl Imrān: 144).

Upon the Messenger’s death, the obligations imposed upon him came to an end. Had he appointed a deputy during his lifetime, that deputy would not have had to be infallible. Indeed, he used to appoint a man to a position of authority, then dismiss him if it became apparent that he had lied, as when he appointed al-Walīd ibn Uqbah ibn Abī Muayt. Even if he had appointed a man as his successor, that man would not have had to be infallible. After his death, the Messenger would neither be a witness over that man nor be responsible for restraining him from whatever he might do, unlike the case of appointing a deputy during his lifetime.

Third Aspect:

It may be said that appointing deputies during one’s lifetime is obligatory upon every holder of authority. Every holder of authority—whether a messenger or an imam—must appoint someone to manage affairs from which he is absent.

He must administer affairs either in person or through his deputy. Whatever affairs he is present to, he can administer himself; as for those from which he is absent, he can administer them only through a deputy whom he appoints over them. He therefore appoints over those of his subjects who are absent from him someone who enjoins what is right, forbids what is wrong, collects the dues they owe, and enforces among them (2)