The Adhan!!

The Adhan is a call to prayer in Islam that announces the start of the prayer time and invites Muslims (two billion Muslims) to participate in the obligation. The Adhan is an important part of religious rituals and is performed loudly in mosques.

Adhan formula:

God is great, God is great (repeated twice)
I bear witness that there is no god but God (repeated twice)
I bear witness that Muhammad is the Messenger of God (repeated twice)
Hayya ala al-Salat (repeated twice)
Hayya ala al-Falāh (repeated twice)
God is great, God is great (repeated once)
La ilaha illa Allah (repeated once)