The Ruling on Responding to the Mu'adhdhin

The Shaykh : Responding to the mu'adhdhin, my brothers, is a confirmed sunnah (recommended practice). The Prophet (peace and blessings be upon him) commanded it and said: Some scholars even said that it is obligatory. Therefore, a person should not be distracted from it, even if he is reciting; he should respond to the mu'adhdhin. The scholars differed on whether a person who is praying should respond to the mu'adhdhin or not. Shaykh al-Islam Ibn Taymiyyah said: He should respond to the mu'adhdhin while he is praying, because all of it is dhikr (remembrance of Allah). Others said: No, he should not respond to the mu'adhdhin, because prayer involves preoccupation, and responding to the mu'adhdhin is long; it is not like the response to a sneeze. When a person sneezes while praying, he says "Alhamdulillah" (Praise be to Allah), but responding to the mu'adhdhin is long and distracts him from the prayer. One should respond to the mu'adhdhin and say what he says, except for two phrases: "Hayya 'ala al-salah" (Come to prayer) and "Hayya 'ala al-falah" (Come to success). For these, we say: "La hawla wa la quwwata illa billah" (There is no power and no strength except with Allah). This means that we disavow our own power and strength except with Allah, and this means that we ask Allah for assistance.
In the Fajr adhan, the mu'adhdhin says: "Al-salah khayrun min al-nawm" (Prayer is better than sleep). What do we say? We say what he says: "Al-salah khayrun min al-nawm," because this is the implication of the generality of the hadith: The Sunnah did not come with an exception except for: "Hayya 'ala al-salah" and "Hayya 'ala al-falah."