Sources for this sermon

SERMON 218

A part of the same sermon about those who went to Basrah to fight Amir al-mu'minin
 

They marched on my officers and the custodians of the public treasury which is still under my control and on the people of a metropolis, all of whom were obedient to me and were in allegiance to me. They created division among them, instigated their party against me and attacked my followers. They killed a group of them by treachery, while another group took up swords against them and fought with the swords till they met Allah as adherents to truth.