( وَمَا كَانَ صَلَاتُهُمْ عِندَ الْبَيْتِ إِلَّا مُكَاءً وَتَصْدِيَةً ) (And their prayer at the House was not except whistling and handclapping): Their prayers took the shape of clapping and whistling.

( فَذُوقُوا الْعَذَابَ بِمَا كُنتُمْ تَكْفُرُونَ) (So taste the punishment for what you disbelieved): The punishment is reserved for those who associate partners with Allah (swt) and deny Him (swt). On the other hand, believers and the obedient will be rewarded. Punishment is inevitable for polytheists who reject and arrogantly refuse faith, and they are considered among the disbelievers.