The Book of Pilgrimage (Kitab Al-Hajj)

Muslim :: Book 7 : Hadith 2943

Usama b. Zaid (Allah be pleased with him) narrated: AHah's Messenger (may peace be upon him) was on his way back from 'Arafat and as he reached the creek (of a hillock) he got down and urinated (Usama did not say that he poured water), but said: He (the Holy Prophet) called for water and performed ablution, but it was not a thorough one. I said: Messenger of Allah, the prayer! Thereupon he said: Prayer awaits you ahead (at Muzdalifa). He then proceeded, until he reached Muzdalifa and observed sunset and 'Isha' prayers (together) there.

Source materials are from the University of Southern California MSA site
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