Musnad Ahmad

It is narrated from Hazrat Abu Huraira (may Allah be pleased with him) that once I set out towards Mount Tur. On the way, I met Ka'b bin Ahbar (may Allah have mercy on him). I sat with him; he began telling me things from the Torah and I began telling him things from the Prophet Muhammad (peace and blessings be upon him). During this, I also narrated this hadith to him: The Prophet Muhammad (peace and blessings be upon him) said, "The best day on which the sun rises is Friday. On this day, Adam was created, on this day he was sent down from Paradise, on this day his repentance was accepted, on this day he died, and on this day the Day of Resurrection will be established. Every creature on the earth becomes fearful on Friday at sunrise, fearing that perhaps today the Resurrection will be established, except for jinn and mankind. And in this day there is an hour in which, if a Muslim servant coincides with it while praying and asks Allah for anything, Allah will surely grant it to him." Ka'b Ahbar (may Allah have mercy on him) said, "This happens only once in the year." I said, "No, it happens every Friday." Upon this, Ka'b opened the Torah and read it, then said, "The Prophet Muhammad (peace and blessings be upon him) has spoken the truth." Hazrat Abu Huraira (may Allah be pleased with him) says that after this, I met Hazrat Abdullah bin Salam (may Allah be pleased with him), so I told him about my sitting with Ka'b and also narrated the hadith I had mentioned regarding Friday, and said that Ka'b said it happens only once in the year. Hazrat Abdullah bin Salam (may Allah be pleased with him) said, "Ka'b made a mistake." I said, "Then Ka'b read the Torah and said, 'No, it happens every Friday.'" Hazrat Ibn Salam (may Allah be pleased with him) then affirmed Ka'b's statement.