Q17: What should be said on hearing the Adhān (prayer call)?

Answer: One should repeat what the muezzin says except when saying: "Hayy ‘ala as-salāh" (come to prayer) and "Hayy ‘ala al-falāh" (come to success). Here, one should say: "La hawla wala quwwata illā billāh" (there is no might nor strength except with Allah). [Agreed upon]