In Arabic, the word ‘Athan’ is to call or to inform. Religionsly, it is a call made to inform people that the time of the prayer has begun. It is obligatory for the congregation in the mosque while for individuals praying alone at home, for example, it is a highly preferred act. It begins by proclaiming the greatness and oneness of Allah and the denial of disbelief and polytheism, testifying to the messengership of Muhammad and then calling to a prosperity which is everlasting, pointing to the return to Allah.

One day, The Messenger of Allah and the Muslims discussed the matter of calling the people to prayer at the exact time. Many opinions put forwarded by the companions of Prophet about the issue. Some suggested the use of a bell like the Christians, others suggested the use of a horn like the Jews, but ‘Umar, may Allah be pleased with him, suggested sending someone to announce the prayer.

Then Allah's Messenger agreed to use a bell, but he, sallallaahu alayhi wa sallam, was not happy to use it because of its similarity with the Christians.

After the Prophet had ordered a bell to be made so that it could be struck to gather the people to Prayer, a companion, Abdullah Ibn Zayd Ibn Abd Rabbih, may Allah be pleased with him, said: "I was sleeping when I saw in my dream that a man carrying a bell in his hands, and I said: "Slave of Allah, will you sell this to me?" Then he asked what I would do with it? I replied that we would use it to call the people to Prayer. He said: "Shall I not guide you to something better than that?" I replied: "Certainly," Then he told me to say the ‘Athan’ and he told me its wordings.

When I told to Messenger in the morning about the vision what I had seen, he said: "It is a true vision, ‘In shaa’Allah’, so get up along with Bilal, and when you have taught him what you have seen, let him use it in making the call to Prayer, for he has a stronger voice than you." So, I got up along with Bilal and began to teach it to him, and he used it in making the call to Prayer.

‘Umar Ibn Al-Khattab, may Allah be pleased with him, heard this when he was in his house, and came out trailing his cloak and said: "Allah's Messenger, by Him Who has sent you with the truth, I have seen the same thing (during sleep) as has been said." To this Allah's Messenger replied: ‘Praise be to Allah!’" [Ahmad and At-Tirmithi]

Many Prophetic narrations describe the virtues of the ‘Athan’ and the one who calls it. The Prophet said: “If the people knew what was in the ‘Athan’ (of virtues and rewards) and the first row (i.e. the first line in congregational prayer), and that they could not get it except by drawing lots, they would draw lots…” [Al-Bukhari]

The Prophet also said: “Your Lord, the Exalted, Says: “Look at my slave there who makes the call to Prayer and establishes the Prayer out of fear of Me. I have forgiven My slave and have allowed him to enter Paradise.” [Ahmad, Abu Dawood and An-Nasa’i]

The Prophet said: “Supplications (offered) in between the (two) calls for prayer (i.e. Athan and Iqamah) will never be rejected." The companions, may Allah be pleased with them, said: "O Prophet of Allah! What should we say?" He said: "Ask Allah the Almighty, to grant pardon (and good health) in both this life and the hereafter."

Allah's Messenger said: “Any person who, on hearing the Athan, supplicates: “Allahumma rabba haathihid-da‘watit-tammati was-salatil-qa’imati, ati Muhammadan al-waseelata wal-fadheelata wab‘ath-hu maqaman mahmudanal-lathee wa‘adtahu. (‘O Allah! Lord of this complete prayer of ours. By the blessing of it, give Muhammad (), his eternal rights of intercession, distinction and highest class (in Paradise). And raise him to the promised rank You have promised him,’ then he will assured of my intercession on the Day of Judgement.)” [Al-Bukhari]