The Treasures of Kisra

The war with Persia, begun under Abu Bakr, reached its turning point under 'Umar. He put Sa'd ibn Abi Waqqas over the army in Iraq, and at al-Qadisiyyah, after days of hard fighting against the Persian general Rustam and his elephants, the Muslims prevailed. The historians tell how 'Umar went out of Madinah each morning to ask passing riders for news.

Before the battle, the historians report, Rustam asked the Muslim envoy Rib'i ibn 'Amir what had brought them. His answer became famous: Allah had sent them to bring whomever He willed from the worship of created beings to the worship of Allah, from the narrowness of this world to its breadth, and from the injustice of religions to the justice of Islam.

Al-Mada'in, the Persian capital, fell soon after. Years before, the Prophet ﷺ had said that when Kisra perished there would be no Kisra after him, and that his treasures would be spent in the path of Allah (Sahih al-Bukhari 3618). At Nahawand in 21 AH the last great Persian army was defeated, and al-Nu'man ibn Muqarrin, who led the Muslims, was martyred. Before the campaigns 'Umar had consulted widely, even questioning the Persian commander al-Hurmuzan, by then a Muslim, on how to proceed (Sahih al-Bukhari 3159).