Early Life
Abdullah b Sa'ad was a foster brother of Uthman. Uthman had drunk milk of the mother of Abdullah b Sa'ad. Under the influence of Uthman, Abdullah b Sa'ad accepted Islam before the conquest of Makkah. He came to Madina, and the Holy Prophet employed him for recording the revelations. He tampered with some of the revelations, and when taken to task he apostatized and returned to Makkah. When the Holy Prophet conquered Makkah he granted general amnesty to the Quraish. An exception was made in the case of ten persons who were to be killed for their heinous crimes. Abdullah b Sa'ad was one of these ten persons who were to be killed. Abdullah b Sa'ad sought the protection of Uthman and appealed to him to intercede on his behalf with the Holy Prophet. The foster mother of Uthman appealed to him to save his foster brother. Uthman was reluctant to intercede because under Islam apostasy was a crime punishable with death. On account of the persistent entreaties of his foster mother for whom he had great respect Uthman agreed that he would do whatever he could. Uthman took Abdullah b Sa'ad to the Holy Prophet, and placed him at the mercy of the Holy Prophet. When the request for forgiveness was made the Holy Prophet made no reply. Uthman repeated the request for the second time and still the Holy Prophet remained silent. The request was made for the third time and out of regard for Uthman, the Holy Prophet agreed to spare the life of Abdullah b, Sa'ad. Abdullah repented and craved for forgiveness. He was forgiven and was readmitted to the fold of Islam.

After reconversion to Islam
After reconversion to Islam, Abdullah b Sa'ad proved to be a good Muslim. He allowed all the injunctions of Islam. He participated in the various battles, and gave a good account of himself. He was intelligent, and was particularly good in revenue collection. Umar was a good judge of men, and impressed by Abdullah's abilities, he appointed him as a Governor of Upper Egypt. As Governor Abdullah b Sa'ad did well and Umar was well pleased with him.