Musayyab ibne Najiyyah relates that one day Imam Ali (a.s.) was reciting a sermon when a man suddenly called out – O oppression! Imam Ali (a.s.) said to him – Come near. He came near and Imam (a.s.) said – I have been oppressed equaling the quantity of the particles of sand in the desert and the hair on the body of animals.
Sharhe Nahj al-Balaaghah v 4 p 106