Hadith 547 a - The Book of Mosques and Places of Prayer - Sahih Muslim - صحيح مسلم - Collection of Actions, Sayings and Teachings of Prophet Muhammad (صلى الله عليه و سلم) - Kutub as-Sittah

5. The Book of Mosques and Places of Prayer - كتاب الْمَسَاجِدِ وَمَوَاضِعِ الصَّلاَةِ

13) Chapter: Forbiddance To Spit In The Mosque While Engaged In Prayer

Abdullah b. Umar reported:

The Messenger of Allah (ﷺ) saw spittle on the wall towards Qibla, and scratched it away and then turning to the people said: When any one of you prays, he must not spit in front of him, for Allah is in front of him when he is engaged in prayer.

Reference: 547 a
English reference: Book 4, Hadith 1116
In-book reference: Book 5, Hadith 61
Grade: Sahih
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13) باب النَّهْىِ عَنِ الْبُصَاقِ، فِي الْمَسْجِدِ فِي الصَّلاَةِ وَغَيْرِهَا ‏‏

حَدَّثَنَا يَحْيَى بْنُ يَحْيَى التَّمِيمِيُّ، قَالَ قَرَأْتُ عَلَى مَالِكٍ عَنْ نَافِعٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم رَأَى بُصَاقًا فِي جِدَارِ الْقِبْلَةِ فَحَكَّهُ ثُمَّ أَقْبَلَ عَلَى النَّاسِ فَقَالَ ‏‏ ‏.‏ "‏ إِذَا كَانَ أَحَدُكُمْ يُصَلِّي فَلاَ يَبْصُقْ قِبَلَ وَجْهِهِ فَإِنَّ اللَّهَ قِبَلَ وَجْهِهِ إِذَا صَلَّى ‏"