Abd-Allah ibn Ubayy, also caled ibn Salul in reference to his mother, (d. 631) was a chief of the
Arab tribe
Banu Khazraj and one of the leading men of
Medina (then known as Yathrib). Upon the arrival of
Muhammad, Ibn Ubayy became a
Muslim, though the sincerity of that conversion is disputed. Because of repeated conflicts with Muhammad, Islamic tradition has labelled him a
Munafiq (hypocrite) and "leader of the Munafiqun".
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