army of Quraysh. Abu Ubayda then later on attacked him and killed him. In the year 625, he participated in the Battle of Uhud. In the second phase of the battle, when Khalid ibn al-Walid's cavalry attacked the Muslims from the rear, changing an Islamic victory into defeat, the bulk of the Muslim soldiers were routed from the battlefield, and few remained steadfast. Abu Ubayda was one of them and he guarded Muhammad from the attacks of the Qurayshi soldiers. On that day, Abu Ubayda lost two of his front teeth while trying to extract two links of Muhammad's armour that had penetrated into his cheeks. Later in the year 627 he took part in the Battle of the Trench and also in the Invasion of Banu Qurayza. He was also made commander of a small expedition that set out to attack and destroy the tribes of Tha'libah and Anmar, who were plundering nearby villages. In the year 628 he participated in Treaty of Hudaybiyyah and was made one of the witnesses over the pact. Later in the same year, he was a part of the Muslim campaign to Khaybar. In the year 630, when the Muslim army conquered Mecca, Abu Ubayda was commanding one of the four divisions that entered the city from four different routes. Later that year, he participated in the Battle of Hunayn and the Siege of Ta'if. He was also part of the Tabuk campaign under the command of Muhammad himself. On their return from the Battle of Tabuk, a Christian delegation from Najran arrived in Medina and showed interest in Islam and asked Muhammad to send them a person to guide them in the matters of religion and in other tribal affairs according to Islamic laws, Abu Ubayda was appointed by Muhammad to go with them. He was also sent as the tax collector () to Bahrain by Muhammad. He was present in Mecca when Muhammad died in 632. In the year 629 Muhammad sent 'Amr ibn al-'As to Daat al-Salaasil from where he called for reinforcements, this was known as the Expedition of Abu Ubayda ibn al-Jarrah. Muhammad sent Abu Ubayda in command of an army that included Abu Bakr and Umar. They attacked and defeated the enemy. Later in the same year, another expedition was sent under his command to locate the routes of Qurayshi caravans. Role in the succession of Abu