'Ubada bin As-Samit

Ubada ibn al-Samit al-Ansari al-Khazraji (RA) was from the Khazraj tribe of Medina and was among those who took the Second Pledge of Aqabah, committing themselves to the Prophet ﷺ before the Hijra. He was one of twelve leaders (nuqaba) appointed among the Ansar at that pledge. He participated in the Battle of Badr and all subsequent major campaigns. He was appointed by Umar ibn al-Khattab (RA) as a teacher and judge in the Levant (al-Sham), where he became one of the most important religious authorities. He narrated approximately 181 hadiths. One of his most famous narrations is the foundational hadith on the bay'a (pledge of allegiance) at Aqabah, in which the Prophet ﷺ stipulated conditions for being Muslim. He also narrated the important hadith on the necessary conditions for valid prayer. He passed away in Syria around 34 AH.