Who said this phrase and how sound is its chain of narration: "You ruled, you were just, you felt secure, so you slept, O Umar; and we ruled, we were unjust, we feared, so we stayed awake, and you, O Muslims, were victorious over us"?

This statement is attributed to Hormuzan, the Persian ruler of Tustar, but its authenticity cannot be definitively confirmed due to the lack of a reliable chain of narration for this exact wording. However, it is mentioned in Tarikh al-Tabari and Al-Bidaya wa al-Nihaya by Ibn Kathir that Hormuzan was sent to Umar in Medina after the conquest of Tustar. He found Umar sleeping in the mosque without guards, and Hormuzan was astonished by his simplicity and lack of guards, saying: "He ought to be a prophet." They replied: "Rather, he acts like the prophets." After Umar woke up, he listened to Hormuzan, who later embraced Islam and resided in Medina, and Umar allocated him a stipend from the public treasury.