Ubadah ibn al-Samit

'Ubadah ibn al-Samit (Arabic: عُبَادَة بۡن ٱلصَّامِت ʿUbādah ibn aṣ-Ṣāmit) was a companion of Muhammad and a well-respected chieftain of the Ansar tribes confederation. He participated in almost every battle during Muhammad's era. His official title, according to Muslim scholarly tradition, was 'Ubadah bin Saamit al-Ansari al-Badri (عُبَادَة بۡن ٱلصَّامِت ٱلۡأَنْصَارِيّ ٱلۡبَدْرِيّ) for his actions at the Battle of Badr. He served under the first three Rashidun caliphs in the Muslim conquest against the Byzantines.

The conquest of Cyprus marked 'Ubadah as one of the Rashidun army's most successful military commanders. He participated in more than seven large scale military campaigns before ending his career as a Qadi in the Holy Land. In later years he assisted the then-governor and later Umayyad caliph Mu'awiya.

'Ubadah served as the Qur'anic teacher of Suffah and the Mufti and judge of the Rashidun caliphate, along with matters of converting subdued populations and building Mosques, such as the Mosque of Amr ibn al-As in Egypt and the Bazaar Congregational mosque in Homs. Despite his low structural position, 'Ubadah's influence as a respected senior Sahabah who was trusted by Muhammad and caliph Umar could rule many of his compatriots, including those who outranked him structurally such as Mu'awiya, who served as Governor of Homs during 'Ubadah's tenure as judge.

Islamic scholars regard 'Ubadah as an influential companion of Muhammad who passed down many Hadiths that became the basis of Fiqh ruling in various matters.