and their prayers before the Temple are nothing but whistling and clapping of hands. Taste then, [O unbelievers,] this chastisement as an outcome of your persistent denial of the truth!

Their prayer at the House (of God) is nothing but whistling and clapping of hands: (Its only answer can be), "Taste ye the penalty because ye blasphemed."

And their worship at the (holy) House is naught but whistling and hand-clapping. Therefore (it is said unto them): Taste of the doom because ye disbelieve.

And their prayer at the House is nothing but whistling and clapping of hands. Taste, then, the chastisement, because you disbelieved.

And their prayer at the House was not except whistling and handclapping. So taste the punishment for what you disbelieved.