Lu'lu' wal-Marjan

Hazrat Abdullah bin Mas'ud (may Allah be pleased with him) narrated that near the Ka'bah, two men from the Quraysh and one from the Thaqif, or one from the Quraysh and two from the Thaqif, were sitting. Their bellies were very large but they were devoid of sense. One of them said, "What do you think, does Allah hear our conversations?" The second said, "If we speak loudly, He hears, but if we speak softly, He does not hear." The third said, "If Allah can hear when we speak loudly, then surely He can also hear when we speak softly." Upon this, the following verse was revealed: "And you cannot hide yourselves from your hearing, nor from your sight, nor from your skins to bear witness against you, but you thought that Allah does not know much of what you do." (Surah Ha Mim As-Sajdah: 22)