How was the prayer carried out after the killing of the Commander of the Faithful?
In the Name of Allah, the All-beneficent, the All-merciful
Numerous historical sources mention that Imam al-Hasan (a) was the one who led the people in congregational prayer in place of his father, the Commander of the Faithful (a), when the accursed Ibn Muljam struck him.
Imam ʿAli (a) bound his head with his waist-wrapper while blood was flowing down his face—and some reports say that the people bound his head. When al-Hasan and al-Husayn entered the mosque, they saw the people trying to help the Imam, in that condition and with his strength drained, to lead them in congregational prayer, but they were unable. When he saw his son al-Hasan (a), he put him forward for the prayer and ordered him to lead the people in prayer.
The reports indicate that Imam ʿAli (a) followed Imam al-Hasan (a) in the prayer, praying seated and performing it by gestures; when Imam al-Hasan (a) finished the prayer, he placed his father’s head in his lap.