(And their worship at the (holy) House is naught but whistling and hand-clapping…) [8:35].
Abu Isma'il ibn 'Amr al-Naysaburi informed us> Hamzah ibn Shabib al-Ma'mari> 'Ubayd Allah ibn Ibrahim ibn Balawayh> Abu'l-Muthanna Mu'adh ibn al-Muthanna> 'Amr>> his father> Qurrah> 'Atiyyah> Ibn 'Umar who said: “They [people in the pre-Islamic period] used to go round the Ka'bah clapping - and he described how they clapped - and whistling - and he described how they whistled - and they also put their cheeks on the ground. Then this verse was revealed”.
Asbab Al-Nuzul by Al-Wahidi , trans. Mokrane Guezzou