Allah has promised those of you who believe and do right actions that He will make them successors in the land as He made those before them successors, and will firmly establish for them their religion with which He is pleased and give them, in place of their fear, security. “They worship Me, not associating anything with Me. Any who are unbelievers after that, such people are deviators.”
(Surat an-Nur, 55)

It was narrated by Ayyasi through Ali ibn Hassan: This verse was read alongside him:  Swear by Allah that they are those who love our Ahl al-Bayt. ALLAH WILL MAKE THEM DO (THIS) BY THE HAND OF A MAN FROM US. THAT MAN IS THE MAHDI OF THIS UMMAH.

Majmau’l bayan fi tafsiri’l-Kuran Abu Ali Eminuddin Fazl, Hasan b. Fazl Tabersi 1986, v: 4, p. 832