Sa'd was
one of the first to embrace Islam. It was said by
Ibn Ishaq that Sa'd was one of several individuals invited to Islam by
Abu Bakr. Sa'd's mother opposed her son's conversion and threatened to go on a
hunger strike until he left Islam, but he did not heed her threat and she finally yielded due to his insistence. Chroniclers reported that Muhammad told Sa'd that God praised his firmness in his faith, but also told him to be kinder to his mother, as
filial piety is an important virtue in
Islam. Sa'd's brother Amir also converted, prompting their mother to undergo another hunger strike, which likewise failed to deter her second son either. According to the
Fath al-Bari of
Ibn Hajar al-Asqalani, Sa'd migrated to Medina before Muhammad along with
Ibn Umm Maktum and
Mus'ab ibn Umayr, where he continued to practice Islam. During a
minor reconnaissance operation under
Ubayda ibn al-Harith in
Rabigh shortly before the
Battle of Badr, the team caught the attention of opposing Qurayshi fighters that began to chase them. Sa'd and his team immediately ran away, with some accounts stating that he performed a
Parthian shot as he retreated. The team returned to Medina unscathed, and Sa'd prided himself on allowing the Muslim scouts to survive. Sa'd also reportedly managed to capture two Qurayshi soldiers during this battle. Realizing how Sa'd was affecting the enemies, Muhammad gathered arrows for him and stood next to him while he continuously shot, allowing the encircled Muslims to retreat.
After Uhud until the Ridda Wars Along with Abu Bakr,
Sa'd ibn Mu'adh, Zubayr ibn al-Awwam,
Bilal ibn Rabah,
Abbad ibn Bishr, and
Abu Ayyub al-Ansari, Sa'd was a member of the
Haras (personal bodyguard) unit of Muhammad. On the same day as the pledge, Sa'd also witnessed the ratification of the
Treaty of Hudaybiyyah that created a
ceasefire or non-aggression pact between Medina and Mecca. Until the
Expedition of Tabuk, Sa'd was recorded as participating in all battles under Muhammad, including the
Battle of the Trench, the
Expedition of al-Muraysi', the
Siege of Khaybar, the
Conquest of Mecca, the
battles in Hunayn and Awtas, and the
Siege of Ta'if.
Ibn al-Jawzi and Nur ad-Din al-Halabi recorded that Sa'd instead joined the
Expedition of Usama bin Zayd along with
Umar,
Sa'id ibn Zayd,
Abu Ubayda ibn al-Jarrah, and
Qatada ibn al-Nu'man. After the rebels were routed, Sa'd joined the army marching towards
Dumat al-Jandal to crush several
Bedouin rebels there. Al-Basalamah stated that Umar gathered 12,000 soldiers in Medina to serve under Sa'd. Before the army could be dispatched from Medina, a message from the Iraq front arrived, stating that Abu Ubayd was
killed in action during the
Battle of the Bridge and the
Rashidun soldiers were forced to withdraw to south-west Iraq. Jarir ibn Abdullah of
al-Bajali and
al-Muthanna ibn Haritha of the
Banu Shayban, as those three commanders have just defeated the
Sassanid vanguard in the
Battle of Buwaib. Sa'd engaged in routine correspondence with the central government in Medina, as Sa'd diligently wrote about all developments, major and trivial, and sent at least two messengers every day to Umar. The caliph responded with a message that forbade Sa'd from preemptive attacks. Islamic sources state that Sa'd sent a series of hostile emissaries to taunt Rostam while waiting to receive reinforcements sent by Abu Ubayda ibn al-Jarrah, who had just won the
Battle of Yarmuk. As Rostam's army marched to the battlefield, Sa'd sent a dozen horsemen as scouts, led by
Tulayha and
Amr ibn Ma'adi Yakrib, who disguised themselves as Iraqi locals. They were to ride deep into Sassanid territory and to the outskirts of
Ctesiphon to gather
intel regarding Rostam's forces. After two days of traveling, the scouts spotted the first vanguards of the army, which they estimated at 70,000. Tulayha and ibn Ma'adi sent the scouts to report their findings to Sa'd, while Tulayha and ibn Ma'adi continued to gather intel by themselves. According to Tulayha, the horses belonged to Rostam. He rejoined ibn Ma'adi and they returned to Sa'd to tell him about the number of enemy forces. Al-Tabari's account of the fighting has formed the basis for many modern-day attempts to reconstruct the events of the battle. According to Sa'd al-Ubaisi's reconstruction of the battle based on al-Tabari's work, the battle occurred over four days, with Sa'd overseeing the battle from a tent overlooking the battlefield and the Sassanids relying upon their
elephant corps: • First day,
the day of Armath: The cavalry aimed for the elephants'
alpha male, which the Muslim army recognized by its brighter skin and their perception that it was seemingly leading the other elephants. The day ended with the elephant corps damaged beyond repair, as most of them were killed along with their riders, while many fled and became uncontrollable, trampling their own comrades and causing massive casualties to the Sassanids. The commander of the elephant corps,
Jalinus, fled the battlefield after the Muslim forces gained upper hand. Sa'd ordered his men to chase and kill Jalinus, as he wanted the elephants to be permanently neutralized. A Tamim horseman named Zahra ibn Hawiyah at-Tamimi chased the elephant commander and killed him. Ibn Kathir's version also states that Hilal killed Rostam. After Rostam's death, al-Qa'qa and his Tamim cavalry were surrounded behind enemy lines, while the Muslim army carried out Sa'd's order to advance. Most of the Sassanid forces broke as the Muslim archers attacked them relentlessly. He appointed Zuhra ibn Hawiyah to the vanguard, which marched first to the north, and replaced Khalid ibn Arfatha with Hashim ibn Utbah, his step-nephew, as his deputy. Khalid was reappointed as the rear guard commander. The Tigris was undergoing a heavy tide at the time and crossing it without boats was impossible for the Rashidun forces. Sa'd was forced to wait until they could cross the river. Sa'd heard that the people of
Mosul had gathered at
Tikrit under a figure named al-Antioch. After they were finished in Tikrit, ibn Mu'tam sent Rabi'i ibn al-Afkal and Arfajah to subdue
Nineveh and Mosul before the news about Antiqa's defeat in Tikrit spread. As Yazdegerd fled to Hulwan, he gathered soldiers and followers in every territory passed until he mustered more than 100,000 soldiers and appointed Mihran as their commander. The army of Mihran dug a large ditch around them as a defense and dwelt in that place with a number of troops, supplies, and equipment. Sa'd requested further instruction from Umar, and the caliph ordered Sa'd to stay in al-Mada'in and appoint Hashim ibn Utbah as the leader of the troops to attack
Jalula. Sa'd executed these instructions and sent Hashim to lead the Rashidun troops to engage Mihran forces in the
Battle of Jalula. Al-Qa'qa was appointed as vanguard, Malik ibn Si'r as right wing, Amr ibn Malik on the left, and Amr ibn Murrah al-Juhani as rearguard. The new
misr was formally called Jund al-Kufah, which was a complex for the Muslim soldiers who settled in that area permanently along with their families. Sa'd made
Kufa his permanent headquarters. Umar then ordered the troops in Kufa to assist the army in Emesa, where Abu Ubaydah and Khalid ibn al-Walid were
besieged by a Christian Arab army under the command of
Heraclius. Sa'd sent al-Qa'qa and several thousand cavalries as reinforcements. As the besiegers of Emesa were repelled, Umar ordered al-Qa'qa to return to Iraq. He refused all of Sa'd's offers of hospitality, and handed him a missive from Umar reminding him that the citadel should be available to the public, suggesting that he move his house. According to Asad Ahmed, the caliph also dispatched several intelligence officers, including a spy named Hashim ibn Walid ibn al-Mughira, to investigate Sa'd's conduct. They found unanimous support and positive impressions from the Kufa residents towards Sa'd, except from the tribes of
Bajila and
Abs. According to al-Basalamah, this was because Umar wanted to minimize any potential scandals. He admitted that he trusted Sa'd, Some narrations state that although Umar removed him from his post as governor, he recommended that the
caliph who succeeded him reinstall Sa'd, since he had not removed Sa'd due to any treachery. Sa'd outlived all of the other
ten to whom Paradise was promised and died at the age of eighty, around the year 674. ==Legacy==