Sunan an-Nasa'i, Book 8, Hadith 36 (In-Book)

It was narrated that Anas said: "The Messenger of Allah said: 'Spitting in the Masjid is a sin, and its expiation is to bury it.'"

أَخْبَرَنَا قُتَيْبَةُ، قَالَ حَدَّثَنَا أَبُو عَوَانَةَ، عَنْ قَتَادَةَ، عَنْ أَنَسٍ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏ "‏ الْبُصَاقُ فِي الْمَسْجِدِ خَطِيئَةٌ وَكَفَّارَتُهَا دَفْنُهَا ‏" ‏ ‏.‏

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