Umar's instructions about Sa'ad b Abi Waqas to his Successor
On his death bed Umar nominated Sa'ad b Abi Waqas as a member of the Committee who were to choose the next Caliph from among themselves. He also left instructions that in case Sa'ad b Abi Waqas was not chosen as the Caliph, he who was chosen as the Caliph should duly compensate Sa'ad b Abi Waqas for his services to Islam. He declared that in 640 C.E. he had deposed Sa'ad from the Governorship of Kufa merely by way of policy and not for any of his faults After the deposition of Sa'ad, Ammar b Yasir was appointed as the Governor of Kufa. He held the office for a short time, and was replaced by Mugheera b Shu'ba as the Governor of Kufa.

Appointment of Sa'ad b Abi Waqas as the Governor of Kuf
Umar left instructions for his successor that no change should be made in the Governors appointed by him for one year and that thereafter his successor was free to make whatever changes he deemed necessary in public interest.

When Uthman became the Caliph, Mugheera b Shu'ba was the Governor of Kufa. True to the instructions of Umar, Uthman allowed the (Governors appointed by Umar to continue in their office. After the expiry of one year, Uthman deposed Mugheera and appointed Sa'ad b Abi Waqas as the Governor of Kufa.

Sa'ad b Abi Waqas as the Governor of Kufa
Back in office, Sa'ad b Abi Waqas tried to win the hearts of the people by his generosity and liberal hospitality. Any one who begged of him anything got what he wanted. On Fridays he gave vast amounts in charity. He made arrangements for the feeding of the travelers and the wayfarers. He awarded special stipends to the orphans and the widows. Because of his liberal policies, the means at the disposal of Sa'ad b Abi Waqas did not satisfy his needs. He was accordingly compelled to obtain a loan from the Bait-ul-Mal. The Baitul-Mal was under the charge of Ibn Masud. Ibn Masud was known for his scrupulous honesty, and for his strictness in financial matters. He allowed the loan to Sa'ad b Abi Waqas on the condition that it was to be repaid within a stipulated period. It was further laid down that the amount should be returned within the specified period, and that no extension should be allowed under any circumstances.