In compliance with the instructions of Umar, Saad bin Abi Waqas sent a delegation of twelve Muslims to offer Islam to Yazdjurd the emperor of Persia. The Muslim delegation included Noman b. Muqrin, Muthanna bin Haritha, Asim b. Amr, and Mugheera bin Zurara.
The Muslim delegation rode to Ctesiphon or al-Madsen the capital of Persia. The Muslims dismounted outside the palace of the emperor. A large crowd of the Persians gathered to stare at the shaggy horses and stern faced hard sons of the desert.
The delegation was ushered into the presence of the emperor Yazdjurd surrounded by interpretors and couriers. The Persians used to prognosticate events by omen. In a playful mood Yazdjurd asked the Muslim envoys what a mantle was called in Arabic. They said that it as called "burd". "Burd" in Persian meant to carry away, and the emperor felt; that the Arabs were to carry away Persia.
Then he asked what was the Arabic name for a whip and they said that it was 'Saut'. He construed it as 'Sokht', which in Persian meant "burned". The emperor felt in his heart that the Muslims were going to burn Persia.
Yezdjurd next asked, 'What compels you to invade our land. Is it because we have left you in peace that you have grown so bold?"
Noman b. Muqrin speaking on behalf of the delegation said that. Allah had been kind to them. God had sent a prophet to them who bad shown them the right way. Under the leadership of the Prophet they had been transformed. They were the chosen people of God, and God had entrusted to them a mission, the mission of spreading the true faith.
"In pursuance of our mission, we call you to our faith. If you accept our faith we will leave you with the Book of God, and leave you to your land. If you are not agreeable to join our faith you should accept our overlordship and pay us 'Jizya'. If this alternative is also not acceptable to you, then the sword will decide the issue between us."
"Don't you recollect that you were the most wretched and most miserable people that the world ever saw. Whenever you showed signs of recalcitrance we had only to issue orders to the commanders of our frontier outposts and they crushed your mutinous spirit."
Thereupon Mugheera bin Zurara said that what the emperor said about the Arabs was true in the days of Ignorance; after the advent of the Prophet things had changed and they were no longer wretched or miserable. It was not hunger or misery that had brought them to Persia. They had come carrying the message of the new faith for them. If the message was accepted they would be happy and treat them as brothers. If they were not inclined to accept the new faith or pay Jizya, then there was no option but fight.
The emperor was enraged at these bold words of the Muslims. He shouted, "But for the fact that envoys are not killed, I would surely have killed you. Know that we are a great people whose history extends over ages and such people are proud of their faith which they would not change. And as regards Jizya, I would put dust in your mouth. And as regards the fight know that we are not afraid of you. Tell your Commander that I am sending Rustam against him with a large force, who will teach you a bitter lesson."
Then Yazdjurd asked a court attendant to fetch a basket of earth. When the basket was brought, addressing the Muslim envoys he said, 'Here is the Jizya for you; carry it".
Asirn b. Amr stepped forward, and carried the basket on his head. Turning to the emperor he said, "You have of your own accord handed over your land to the Muslims. We accept your gift."
Thereafter the Muslim envoys rode back at great speed to the Muslim camp carrying the basket of the earth of Persia.
Immediately thereafter Rustam saw Yazdjurd, and the emperor told him that he had given the Muslim envoys dust to carry. Rustam said that was a bad omen for it signified that the Muslims had carried away Persia.
Rustam sent off a group of horsemen to pursue the Muslim envoys and get the fateful basket containing the dust of Persia back from them. To these horsemen Rustam said, "Proceed with the speed of lightning and snatch your mother-earth from the Muslims. lf you recover the basket our land will be safe; if you fail then we are doomed."
The Persian party set off at a brisk pace in pursuit of the Muslim envoys, but they could not catch the Muslims. The Muslims crossed the Ateeq bridge to safety long before the Persians could arrive at the bridge head. The Persians returned crest fallen to report to Rustam the failure of their mission.
In the Muslim camp, there was rejoicing. Presenting the basket containing the dust of Persia to Saad b. Abi Waqas Asim b. Amr said:
"Commander Allah has given us the keys of their kingdom. Rejoice for this is a sign that we are going to conquer their land."
In the Persian camp, Rustam sulked and muttered to himself:
"The enemy has snatched away the keys of our kingdom."