It is narrated from Sayyiduna Abu Musa al-Ash'ari (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said: "This Ummah will be gathered in three groups: one group will enter Paradise without reckoning; the second group will be given an easy reckoning; and some others will come carrying on their backs (the burden of sins) like firm mountains. Allah Almighty will ask about them, though He knows best, and will say: 'These are among My servants who did not associate anyone with Me, while upon their backs are errors and sins. Take these sins off them and put them upon the Jews and the Christians,' and (He will say to them): 'Enter Paradise by My mercy.'" This hadith is sahih (authentic) on the condition of Imam Muslim, but the two Shaykhs (Bukhari and Muslim) did not record it.