Sahih Muslim
Sahih Muslim 703 e
Departing from 'Arafat to Al-Muzdalifah. It is recommended to pray Maghrib and 'Isha together in Al-Muzdalifah on this night
Arabic hadith text
وَحَدَّثَنَا يَحْيَى بْنُ يَحْيَى، قَالَ قَرَأْتُ عَلَى مَالِكٍ عَنِ ابْنِ شِهَابٍ، عَنْ سَالِمِ بْنِ، عَبْدِ اللَّهِ عَنِ ابْنِ عُمَرَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلمصَلَّى الْمَغْرِبَ وَالْعِشَاءَ بِالْمُزْدَلِفَةِ جَمِيعًا .
Translation
Ibn Umar (Allah be pleased with them) reported that Allah's Messenger (ﷺ) observed the sunset and 'Isha' prayers together at Muzdalifa.