It is narrated from Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) that he said: Some people from among the polytheists (who had committed a great deal of killing and a great deal of fornication) said: "O Messenger of Allah! The religion to which you invite us is very good; if only you would tell us that there is also an expiation for the sins we have committed (in the past)!" So Allah, the Mighty and Majestic, revealed this verse: "And those who do not invoke another deity along with Allah" [Surah al-Furqan: 68] , and this verse was also revealed: "Say: O My servants who have transgressed against themselves, do not despair of the mercy of Allah" [Surah al-Zumar: 53] . This hadith is sahih (authentic) on the condition of the two Shaykhs (Bukhari and Muslim), but they did not record it.