Hadith 694 a - The Book of Prayer - Travellers - Sahih Muslim - صحيح مسلم - Collection of Actions, Sayings and Teachings of Prophet Muhammad (صلى الله عليه و سلم) - Kutub as-Sittah

6. The Book of Prayer - Travellers - كتاب صلاة المسافرين وقصرها

2) Chapter:

Salim b. 'Abdullah (b. 'Umar) reported on the authority of his father that Allah's Messenger (way peace be upon him) observed the prayer of a traveller, i. e. two rak'ahs in Mina, and other places; so did Abu Bakr and 'Umar, and 'Uthman too observed two rak'abs at the beginning of his caliphate, but he then completed four.

Reference: 694 a
English reference: Book 4, Hadith 1477
In-book reference: Book 6, Hadith 21
Grade: Sahih
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2) باب قَصْرِ الصَّلاَةِ بِمِنًى ‏‏

وَحَدَّثَنِي حَرْمَلَةُ بْنُ يَحْيَى، حَدَّثَنَا ابْنُ وَهْبٍ، أَخْبَرَنِي عَمْرٌو، وَهُوَ ابْنُ الْحَارِثِ عَنِ ابْنِ شِهَابٍ، عَنْ سَالِمِ بْنِ عَبْدِ اللَّهِ، عَنْ أَبِيهِ، عَنْ رَسُولِ اللَّهِ صلى الله عليه وسلم أَنَّهُ صَلَّى صَلاَةَ الْمُسَافِرِ بِمِنًى وَغَيْرِهِ رَكْعَتَيْنِ وَأَبُو بَكْرٍ وَعُمَرُ وَعُثْمَانُ رَكْعَتَيْنِ صَدْرًا مِنْ خِلاَفَتِهِ ثُمَّ أَتَمَّهَا أَرْبَعًا ‏.‏