All believers are but brethren. Hence, [whenever they are at odds,] make peace between your two brethren, and remain conscious of God, so that you might be graced with His mercy.
Al-Hujurat (The Dwellings) Verse 10
Allah's Apostle said, "Whenever you hear the Adhan, say what the Mu'adhdhin is saying.
Sahih Bukhari: Volume 1, Book 11, Number 585