Abdullah bin Masud reported,

I was concealed behind the curtains of the Kaabah when three men approached, one from Thaqif and his two brothers-in-law from Quraysh. Their bellies were heavy with fat, but their hearts had little understanding. They began conversing among themselves.One of them said, "Do you think Allah hears what we are saying?"Another replied, "I think He hears us when we raise our voices, but does not hear when we lower them."The third said, "If He hears any of it, He surely hears all of it."I mentioned this to the Messenger of Allah ﷺ, and Allah revealed, "And you were not concealing yourselves lest your hearing, your sight, and your skins should bear witness against you, but you assumed that Allah does not know much of what you do" [Fussilat 41:22].

حدثنا عبد الرزاق أخبرنا سفيان عن الأعمش عن عمارة عن وهب بن ربيعة

عن عبد الله بن مسعود قال

إني لمستتر بأستار الكعبة إذ جاء ثلاثة نفر ثقفي وختناه قرشيان كثير شحم بطونهم قليل فقه قلوبهم فتحدثوا بينهم بحديث قال فقال أحدهم ترى أن الله عز وجل يسمع ما قلنا قال الآخر أراه يسمع إذا رفعنا ولا يسمع إذا خفضنا قال الآخران كان يسمع شيئا منه إنه ليسمعه كله قال فذكرت ذلك لرسول الله ﷺ قال فأنزل الله عز وجل {وما كنتم تستترون أن يشهد عليكم سمعكم حتى الخاسرين}