BAYHAQI 5437:
from ʿUthmān b. ʿAffān Atam al-Ṣalāh Biminá from Ajl al-Aʿrāb Liʾannahum Kathurūā ʿĀmaʾidh Faṣallá Bi-al-Nnās Arbaʿ Liyuʿlimahum —
Uthman offered complete prayer at Mina for the sake of bedouins who attended (hajj) in large numbers that year. He led the people four rak'ahs in prayer in order to teach them that the prayer (i.e. noon or afternoon prayer) essentially contained four rak'ahs. (Using translation from Abū Dāʾūd 1964)
البيهقي ٥٤٣٧:
عن عثمان بن عفان اتم الصلاه بمنى عن اجل الاعراب لءنهم كثروا عامءذ فصلى ب-الناس اربع ليعلمهم —
أَنَّ الصَّلَاةَ أَرْبَعٌ
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