The Book of Occultation — al-Ṭūsī · Hadith 90 (#Ḥadīth #7)

30- قال: وحدثني بحر بن زياد الطحان عن محمد بن مروان عن أبي جعفر عليه السلام قال: قال رجل: جعلت فداك، إنهم يروون أن أمير المؤمنين عليه السلام قال بالكوفة على المنبر: لو لم يبق من الدنيـا إلا يوم لطوّل الله ذلك اليوم حتى يبعث الله رجلاً مني يملأها قسطاً وعدلاً كما ملئت ظلما وجورا. فقال أبو جعفر عليه السلام: نعم. قال: فأنت هو؟ فقال: لا،ذاك سمي فالق البحر.

H 30 - Narrated to me Bahar bin Ziyad Tahan from Muhammad bin Marwan that he said: A man asked Imam Muhammad Baqir : May I be your ransom, people say that Amirul Momineen said from the pulpit of Kufa: Even if a single day remains from the tenure of the world, Allah, the Mighty and the High, would prolong that day to such an extent that a man from my progeny will appear; he would fill the earth with justice and equity, just as it would have been fraught with injustice and oppression. Imam Muhammad Baqir said: Yes, His Eminence said so. He asked: Are you that one? Imam replied: No, he would be the namesake of one who split the sea.

Gradings are classical jarḥ-wa-taʿdīl, name-matched to a rijāl index (not individually re-verified).