Al-Awliyaa' is the plural of waliy, which means a true, sincere believer. But the waliy as defined by the leader of the Tijaniyyah Order is he whom Allah distinguishes by handling his affairs and permitting him to witness His Divine deeds and attributes(!)
The conditions of “witnessability” and “distinguishability” produce a very ambiguous definition, since we know that Allah the Exalted does not take anyone other than a pious believer for waliy, and piety can be maintained by the acquisition and application of the knowledge of Allah and His names and attributes as stated in the Qur’an and the Sunnah, in which lawful things are clearly distinct from unlawful.
Ahmad al-Tijani was asked: “Who is harder to know, Allah the Exalted or the waliy?”
“To know the waliy is harder than to know Allah the Exalted,” he said, “due to the fact that the qualities of Allah are distinguished from those of His creatures, whereas the waliy'squalities are identical to those of his fellow human beings with regards to eating, drinking, marrying and the like. It follows that he can be detected and recognized only by the elite.”
He further elaborated:
“If the waliy revealed himself to people, they would worship him, because he would be stripped of his human qualities and equipped with divine qualities internally as well as externally.”(76)