The last successor in the Quran
“(And remember) when Abraham was tested by his lord with certain words and he fulfilled them…”
Mufaddal says that I asked Imam Sadiq (PBUH), “What does “words” mean in this verse?” the Imam said: “The same words which Adam learnt from his Lord and repented. When he said: “O Lord, for the sake of Muhammad, Ali, Fatima, Hassan and Hussein, accept my repentance, and his repentance was accepted. He accepts repentance and He is merciful.” He again asked the Imam: “What does “َفأتَمَّهُن” mean? Imam said: “Allah completed them to 12 Imams, the last one of whom is # the Qa’im.
Al-Burhan Fi Tafsir al-Quran, vol. 1, p. 317
Kamāl al-Dīn, vol. 2, p. 358
The text from : islampfr.com