Narrated `Abdullah: I asked Allah's Apostle "What is the biggest sin in the sight of Allah?" He said, "To set up rivals unto Allah though He alone created you." I said, "In fact, that is a tremendous sin," and added, "What next?" He said, "To kill your son being afraid that he may share your food with you." I further asked, "What next?" He said, "To commit illegal sexual intercourse with the wife of your neighbor."

Narrated `Abdullah: Two person of Bani Thaqif and one from Quarish (or two persons from Quraish and one from Bani Thaqif) who had fat bellies but little wisdom, met near the Ka`ba. One of them said, "Did you see that Allah hears what we say? " The other said, "He hears us if we speak aloud, but He does not hear if we speak in stealthy quietness (softly)." The third fellow said, "If He hears when we speak aloud, then He surely hears us if we speak in stealthy quietness (softly)." So Allah revealed the Verse:-- 'And you have not been screening against yourselves, lest your ears, and your eyes and your skins should testify against you..." (41.22)

Narrated `Ali: While the Prophet was in a funeral procession, he took a stick and started scraping the earth with it and said, "There is none of you but has his place assigned either in Hell or in Paradise." They (the people) said, "Shall we not depend upon that (and give up doing any deeds)?' He said, " Carry on doing (good deeds) for everybody will find it easy to do such deeds as will lead him to his destined place for which he has been created ." (And then the Prophet recited the Verse):-- 'As for him who gives (in charity) and keeps his duty to Allah...' (92.5)