What is the meaning of the complete sentence: "Two nights have passed, and four remain, the well of Aris, and what is the well of Aris?"

Zayd ibn Kharijah spoke at the time of his death, two years into Uthman's caliphate, saying, "Two nights have passed, and four remain." This meant that two years had passed since Uthman became caliph, and four years remained, during which the people of Iraq would be alienated, dissenting, and impugning their governor, Al-Walid ibn Uqbah. Uthman's ring fell into the well of Aris six years into his caliphate, in the 30th year of the Hijra, leading to the emergence of tribulations and a change in the state of the subjects.