The main purpose behind the multiple loud pronouncements of adhan in every mosque is to make available to everyone an easily intelligible summary of Islamic belief. It is intended to bring to the mind of every believer and non-believer the substance of Islamic beliefs, or its spiritual ideology. In modern times, loudspeakers have been installed on minarets for this purpose.
While listening to the adhan, Muslims repeat the same words silently, except when the muezzin says ḥayya 'alas-salāh or ḥayya 'alal-falāḥ they silently say lā hawla wa lā quwata illā billāh (there is no strength or power except from God).
In some parts of the world, such as non Muslim countries like the United Kingdom, the adhan is played only three times a day.