Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) narrates that he never saw the Prophet (peace and blessings be upon him) not fasting on a Friday.
Al-Bazzar recorded it. Its chain contains Layth bin Abi Sulaym, who is thiqah (trustworthy) but a mudallis (one who conceals defects in the chain).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الصيام / 5215
Hadith Gradingمحدثین:إسناده ضعیف
Hadith Takhrij«اخرجه البزار فى المسند (1070) ، أخرجه مسند البزار برقم: 1818، وأخرجه البحر الزخار المعروف بمسند البزار 10 - 18 برقم: 4876»