Sunan Abi Dawud 3861
سنن أبي داود#3861Hasanحَدَّثَنَا أَبُو تَوْبَةَ الرَّبِيعُ بْنُ نَافِعٍ، حَدَّثَنَا سَعِيدُ بْنُ عَبْدِ الرَّحْمَنِ الْجُمَحِيُّ، عَنْ سُهَيْلٍ، عَنْ أَبِيهِ، عَنْ أَبِي هُرَيْرَةَ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " مَنِ احْتَجَمَ لِسَبْعَ عَشْرَةَ وَتِسْعَ عَشْرَةَ وَإِحْدَى وَعِشْرِينَ كَانَ شِفَاءً مِنْ كُلِّ دَاءٍ " .
Narrated Abu Hurayrah: The Prophet (ﷺ) said: If anyone has himself cupped on the 17th, 19th and 21st it will be a remedy for every disease
Scholarly Authentication
The label above is the grade most of these scholars gave — 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. Each scholar's own wording:
Al-AlbaniHasan
Muhammad Muhyi Al-Din Abdul HamidHasan
Zubair Ali ZaiIsnaad Hasan
In-book reference: 29:7