Sunan Abi Dawud 474
سنن أبي داود#474Sahihحَدَّثَنَا مُسْلِمُ بْنُ إِبْرَاهِيمَ، حَدَّثَنَا هِشَامٌ، وَشُعْبَةُ، وَأَبَانُ، عَنْ قَتَادَةَ، عَنْ أَنَسِ بْنِ مَالِكٍ، أَنَّ النَّبِيَّ صلى الله عليه وسلم قَالَ " التَّفْلُ فِي الْمَسْجِدِ خَطِيئَةٌ وَكَفَّارَتُهُ أَنْ تُوَارِيَهُ " .
Anas b. Malik reported the Prophet(ﷺ) as saying:Spitting in the mosque is a sin and it is expiated by burying the spittle
Scholarly Authentication
The label above is the grade most of these scholars gave, each scholar counted once — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. When they judged only its chain of narrators (“Isnaad”), the label says “Sound chain”. Each scholar's own wording:
Our source also lists this ruling under Muhammad Muhyi Al-Din Abdul Hamid, the editor of the printed edition it was taken from. It is al-Albani's ruling printed again, so it is counted once.
In-book reference: 2:84