"الْحُجامةُ عَلَى الرِّيق أَمْثَلُ، وَفِيها شفاءٌ وَبَرَكَةٌ، وَتَزيدُ في الْحِفْظ وفي الْعَقْل، فاحْتَجَمُوا عَلَى بَرَكَةِ الله يَوْمَ الْخَميس واجتَنبوُا الحجَامَةَ يوْم الْجُمُعَة وَالسَّبْت والأَحَدِ، واحْتَجمُوا يومَ الاثْنَين والثُّلَاثَاءِ، فَإنَّهُ الْيَوم الذِى عَافَى اللهُ فيه أَيُّوبَ منَ الْبَلاءِ، واجْتَنبُوا الحجَامَةَ يَوْم الأرْبَعَاءِ، (فإنَّهُ الْيَوم الَّذي ابْتُلى فيه أَيوبَ وَمَا يبدو جُذَامُ، ولا بَرْصُ إِلَّا في يَوْمِ الأَرْبَعاءِ أو في لَيلَةِ الأَربعاءِ" .
“O Nafi’! The blood is boiling in me, find me a cupper, but let it be someone gentle if you can, not an old man or a young boy. For I heard the Messenger of Allah ﷺ say: ‘Cupping on an empty stomach is better, and in it there is healing and blessing, and it increases one’s intellect and memory. So have yourselves cupped for the blessing of Allah on Thursdays, and avoid cupping on Wednesdays, Fridays, Saturdays and Sundays. Have yourselves cupped on Mondays and Tuesdays, for that is the day on which Allah relieved Ayyub of Calamity, and He inflicted calamity upon him on a Wednesday, and leprosy and leucoderma only appear on Wednesdays, or on the night of Wednesday.”
يَا نَافِعُ قَدْ تَبَيَّغَ بِيَ الدَّمُ فَالْتَمِسْ لِي حَجَّامًا وَاجْعَلْهُ رَفِيقًا إِنِ اسْتَطَعْتَ وَلاَ تَجْعَلْهُ شَيْخًا كَبِيرًا وَلاَ صَبِيًّا صَغِيرًا فَإِنِّي سَمِعْتُ رَسُولَ اللَّهِ ﷺ يَقُولُ الْحِجَامَةُ عَلَى الرِّيقِ أَمْثَلُ وَفِيهِ شِفَاءٌ وَبَرَكَةٌ وَتَزِيدُ فِي الْعَقْلِ وَفِي الْحِفْظِ فَاحْتَجِمُوا عَلَى بَرَكَةِ اللَّهِ يَوْمَ الْخَمِيسِ وَاجْتَنِبُوا الْحِجَامَةَ يَوْمَ الأَرْبِعَاءِ وَالْجُمُعَةِ وَالسَّبْتِ وَيَوْمَ الأَحَدِ تَحَرِّيًا وَاحْتَجِمُوا يَوْمَ الاِثْنَيْنِ وَالثُّلاَثَاءِ فَإِنَّهُ الْيَوْمُ الَّذِي عَافَى اللَّهُ فِيهِ أَيُّوبَ مِنَ الْبَلاَءِ وَضَرَبَهُ بِالْبَلاَءِ يَوْمَ الأَرْبِعَاءِ فَإِنَّهُ لاَ يَبْدُو جُذَامٌ وَلاَ بَرَصٌ إِلاَّ يَوْمَ الأَرْبِعَاءِ أَوْ لَيْلَةَ الأَرْبِعَاءِ
“Ibn ‘Umar said: ‘O Nafi’! The blood is boiling in me. Bring me a cupper and let him be a young man, not an old man or a boy.’ Ibn ‘Umar said: ‘I heard the Messenger of Allah ﷺ say: “Cupping on an empty stomach is better, and it increases one’s intellect and memory. And it increases the memory of one who has a good memory so whoever wants to be cupped, (let him do it) on a Thursday, in the Name of Allah. Avoid cupping on Fridays, Saturdays and Sundays. Have yourselves cupped on Mondays and Tuesdays, and avoid cupping on Wednesdays, for that is the day on which the calamity befell Ayyub, and leprosy and leucoderma only appear on Wednesday or the night of Wednesday.”
سَمِعْتُ رَسُولَ اللَّهِ ﷺ يَقُولُ الْحِجَامَةُ عَلَى الرِّيقِ أَمْثَلُ وَهِيَ تَزِيدُ فِي الْعَقْلِ وَتَزِيدُ فِي الْحِفْظِ وَتَزِيدُ الْحَافِظَ حِفْظًا فَمَنْ كَانَ مُحْتَجِمًا فَيَوْمَ الْخَمِيسِ عَلَى اسْمِ اللَّهِ وَاجْتَنِبُوا الْحِجَامَةَ يَوْمَ الْجُمُعَةِ وَيَوْمَ السَّبْتِ وَيَوْمَ الأَحَدِ وَاحْتَجِمُوا يَوْمَ الاِثْنَيْنِ وَالثُّلاَثَاءِ وَاجْتَنِبُوا الْحِجَامَةَ يَوْمَ الأَرْبِعَاءِ فَإِنَّهُ الْيَوْمُ الَّذِي أُصِيبَ فِيهِ أَيُّوبُ بِالْبَلاَءِ وَمَا يَبْدُو جُذَامٌ وَلاَ بَرَصٌ إِلاَّ فِي يَوْمِ الأَرْبِعَاءِ أَوْ لَيْلَةِ الأَرْبِعَاءِ
[Machine] I heard the Messenger of Allah ﷺ saying, "Cupping on an empty stomach is the most beneficial. It brings blessings and healing, increases intelligence, and improves memory. Get cupped on Thursday for the blessings of Allah Almighty, and avoid cupping on Friday, Saturday, and Sunday. Get cupped on Monday and Tuesday, as it is the day when Allah cured Job from his afflictions. There will be no contagious disease or leprosy except on Wednesday and Wednesday night. Indeed, Job was afflicted on Wednesday." All the narrators of this hadith are trustworthy except for Usman ibn Ja'far, as I don't know about his reliability or integrity.
سَمِعْتُ رَسُولَ اللَّهِ ﷺ يَقُولُ «الْحِجَامَةُ عَلَى الرِّيقِ أَمْثَلُ وَفِيهِ بَرَكَةٌ وَشِفَاءٌ يَزِيدُ فِي الْعَقْلِ وَيَزِيدُ الْحَافِظَ حِفْظًا وَاحْتَجِمُوا عَلَى بَرَكَةِ اللَّهِ تَعَالَى يَوْمَ الْخَمِيسِ وَاجْتَنِبُوا يَوْمَ الْجُمُعَةِ وَيَوْمَ السَّبْتِ وَيَوْمَ الْأَحَدِ وَاحْتَجِمُوا يَوْمَ الِاثْنَيْنِ وَالثُّلَاثَاءِ فَإِنَّهُ الْيَوْمُ الَّذِي عَافَى اللَّهُ فِيهِ أَيُّوبَ مِنَ الْبَلَاءِ وَلَيْسَ يَبْدُو بَرَصٌ وَلَا جُذَامٌ إِلَّا يَوْمَ الْأَرْبِعَاءِ وَلَيْلَةَ الْأَرْبِعَاءِ وَإِنَّمَا ابْتُلِيَ أَيُّوبُ يَوْمَ الْأَرْبِعَاءِ» رُوَاةُ هَذَا الْحَدِيثِ كُلُّهُمْ ثِقَاتٌ غَيْرَ عُثْمَانَ بْنِ جَعْفَرٍ هَذَا فَإِنِّي لَا أَعْرِفُهُ بِعَدَالَةٍ وَلَا جَرْحٍهو واه
“Ibn ‘Umar said: ‘O Nafi’! The blood is boiling in me. Bring me a cupper and let him be a young man, not an old man or a boy.’ Ibn ‘Umar said: ‘I heard the Messenger of Allah ﷺ say: “Cupping on an empty stomach is better, and it increases one’s intellect and memory. And it increases the memory of one who has a good memory so whoever wants to be cupped, (let him do it) on a Thursday, in the Name of Allah. Avoid cupping on Fridays, Saturdays and Sundays. Have yourselves cupped on Mondays and Tuesdays, and avoid cupping on Wednesdays, for that is the day on which the calamity befell Ayyub, and leprosy and leucoderma only appear on Wednesday or the night of Wednesday.” (Using translation from Ibn Mājah 3488)
سَمِعْتُ رَسُولَ اللَّهِ ﷺ يَقُولُ «الْحِجَامَةُ عَلَى الرِّيقِ أَمْثَلُ وَفِيهَا شِفَاءٌ وَبَرَكَةٌ وَهِيَ تَزِيدُ فِي الْعَقْلِ وَتَزِيدُ فِي الْحِفْظِ وَتَزِيدُ الْحَافِظَ حِفْظًا فَمَنْ كَانَ مُحْتَجِمًا عَلَى اسْمِ اللَّهِ فَلْيَحْتَجِمْ يَوْمَ الْخَمِيسِ وَاجْتَنِبُوا الْحِجَامَةَ يَوْمَ الْجُمُعَةِ وَيَوْمَ السَّبْتِ وَيَوْمَ الْأَحَدِ وَاحْتَجِمُوا يَوْمَ الِاثْنَيْنِ وَيَوْمَ الثُّلَاثَاءِ فَإِنَّهُ الْيَوْمُ الَّذِي صَرَفَ اللَّهُ عَنْ أَيُّوبَ فِيهِ الْبَلَاءَ وَاجْتَنِبُوا الْحِجَامَةَ يَوْمَ الْأَرْبِعَاءِ فَإِنَّهُ الَّذِي ابْتَلَى اللَّهُ أَيُّوبَ فِيهِ بِالْبَلَاءِ وَمَا يَبْدُو جُذَامٌ وَلَا بَرَصٌ إِلَّا فِي يَوْمِ الْأَرْبِعَاءِ أَوْ فِي لَيْلَةِ الْأَرْبِعَاءِ»