Sayyiduna Thawban (may Allah be pleased with him) said that the Prophet (peace and blessings be upon him) passed by a man who was being cupped at the cupper's while he was backbiting another man, and the Messenger of Allah (peace and blessings be upon him) said: "The cupper and the cupped have broken their fast."
His words "while he was backbiting another man" I have recorded only in this hadith. Others besides Yazid narrated it from Abu al-Ash'ath, from Shaddad bin Aws, without this phrase, and Abu Asma' al-Rahabi narrated it from Thawban without this phrase.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8303
Hadith Gradingمحدثین:ضعيف جداً
Hadith Takhrij«ضعيف جداً۔ اخرجه الطبراني في الكبير»