35وَما كانَ صَلاتُهُم عِندَ البَيتِ إِلّا مُكاءً وَتَصدِيَةً ۚ فَذوقُوا العَذابَ بِما كُنتُم تَكفُرونَMuhammad Asadand their prayers before the Temple are nothing but whistling and clapping of hands.1Taste then, [O unbelievers,] this chastisement as an outcome of your persistent denial of the truth!2I.e., devoid of all spiritual contents. Some of the early authorities maintain that dancing around the Ka'bah, accompanied by whistling and hand-clapping, was actually a ritual practiced by the pre-Islamic Arabs. Although this explanation is quite plausible, it would appear from the context that the expression "whistling and clapping of hands" is used here metaphorically, to denote the spiritual emptiness of the religious rituals of people who are wont to attribute a quasi-divine efficacy to all manner of circumstantial "forces" - like wealth, power, social status, "luck", etc.The chastisement or suffering referred to here was their crushing defeat at Badr.