As soon as the battle of Qadisiyya was over, Sa'ad sent a report of the victory of the Muslims to Umar. In the report, Sa'ad observed:
"Allah the Mighty has given us victory over the enemy after prolonged and fierce battle. The enemy was in great number and strength, but Allah in His Mercy has granted victory to the Muslims. For this Allah and His l' ophet be praised."
The report was accompanied by a list of casualties as well as the immediate spoils that had fallen in the hands of the Muslims.
The report was sent through a special messenger. The courier selected for the mission was Sa'ad b. Umeila of the Bani Fazara, a clan that lived to the north of Madina.
The courier was provided a fast camel. He was also given provisions for the journey. He was commissioned to ride post haste to Madina, and tell the Caliph and the Muslims the happy news of the victory of the Muslims at the historic battle of Qadisiyya.
From Qadisiyya, Madina was about a thousand miles. Riding day and night, with very short spells of rest, Saad b. Umeila covered the distance in a fortnight. The sun had just risen when the courier reached the outskirts of Madina.
When about two miles from Madina, the courier came upon a man sitting by the roadside who stood up at the approach of the camel rider and asked him from where did he come. Sa'ad b. Umeila said that he was coming from Iraq.
The man who accosted the camel driver was Umar. So keen was Umar about getting the news of the result of the battle of Qadisiyya that Umar would every day in the morning walk for a few miles from Madina on the way to Iraq hoping that some courier would come carrying the news. For the last one week this was the usual practice with Umar. When the sun rose high, and no traveller from Iraq appeared the Caliph would return to Madina. At Madina day and night the faithful prayed for the victory of the Muslims in the battle of Qadisiyya.
When Sa'ad b. Umeila said that he was coming from Iraq, Umar did not reveal his identity to him. Excitedly he asked, "What news do you carry about the battle of Qadisiyya." Sa'ad said exultantly, "God has given the Muslims victory. "
Umar's face lit up with joy as he heard the news of the victory of the Muslims. He did not tell the courier that he was the Caliph and that the report that he carried was meant for him.
The courier quickened the pace of the camel so that he might reach Madina as early as possible. Umar started running alongside the camel, and kept on asking the camel rider the details about the Muslim victory, Sa'ad furnished the necessary details. When Saad had related all that he could tell, Umar exclaimed "Glory be to Allah", and Sa'ad also said, "God be praised."
By this time they had reached Madina, and seeing Umar, the Madinites gathered round him and greeted him as "Amir-ul-Mominin." Thereupon the courier felt embarrassed and turning to Umar said, "O Commander of the Faithful, why did you not reveal your identity to me?"
Umar said, "Brother, be at rest. No blame rests on you."
Sa'ad then handed over the report of Sa'ad b. Abi Waqqas. As Umar read the report, tears of joy trickled from his eyes. All the Muslims of Madina gathered in the Prophet's Mosque. There Umar read the report of Saad b. Abi Waqqas to the congregation. Then the Muslims led by Umar offered a special prayer of thanksgiving to God for the victory of the Muslims at the battle of Qadisiyya.