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. He participated in almost every battle during Muhammad's era. His official title, according to Muslim scholarly tradition, was 'Ubadah ibn 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 campaigns against the Byzantine Empire.

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 Mu'awiya ibn Abi Sufyan, the governor of Syria and future founder of the Umayyad Caliphate.

'Ubadah served as the Quranic teacher of the Suffah, as well as the mufti and judge of the Rashidun Caliphate, and was involved in the matters of converting subdued populations and building mosques, such as the Amr ibn al-As Mosque in Egypt and the Congregational mosque in Homs. Despite his low structural position, 'Ubadah's influence as a respected senior sahaba who was trusted by Muhammad and Caliph Umar could over-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.