Hadith 908 - The Book of Prayer - Eclipses - Sahih Muslim - صحيح مسلم - Collection of Actions, Sayings and Teachings of Prophet Muhammad (صلى الله عليه و سلم) - Kutub as-Sittah

10. The Book of Prayer - Eclipses - كتاب الكسوف

4) Chapter: Those Who Say That He Prayed With Eight Bowings And Four Prostrations

Ibn 'Abbas reported:

When there was a solar eclipse the Messenger of Allah (way peace be upon him) observed eight ruku's and four prostrations (in two rak'ahs). This has been narrated by 'Ali also.

Reference: 908
English reference: Book 4, Hadith 1984
In-book reference: Book 10, Hadith 20
Grade: Sahih
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4) باب ذِكْرِ مَنْ قَالَ إِنَّهُ رَكَعَ ثَمَانَ رَكَعَاتٍ فِي أَرْبَعِ سَجَدَاتٍ ‏

حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا إِسْمَاعِيلُ ابْنُ عُلَيَّةَ، عَنْ سُفْيَانَ، عَنْ حَبِيبٍ، عَنْ طَاوُسٍ، عَنِ ابْنِ عَبَّاسٍ، قَالَ صَلَّى رَسُولُ اللَّهِ صلى الله عليه وسلم حِينَ كَسَفَتِ الشَّمْسُ ثَمَانَ رَكَعَاتٍ فِي أَرْبَعِ سَجَدَاتٍ ‏.‏ وَعَنْ عَلِيٍّ مِثْلُ ذَلِكَ ‏.‏