The virtue of the muezzins

It is narrated from Sayyiduna Abu Hurayrah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "Indeed, the most beloved of the servants of Allah Almighty to Allah, the Mighty and Majestic, are those who closely observe and watch the movement of the sun and the moon (to know the times of prayer and fasting)."
In the hadith of Sayyiduna Bilal (may Allah be pleased with him) it is narrated that the Prophet (peace and blessings be upon him) said to him: "There is nothing better than this deed of yours (giving the adhan) except jihad in the path of Allah."
This narration will come later, if Allah Almighty wills, in the section on the virtue of jihad.

It is narrated from Sayyiduna Abu Hurayrah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) used to say: "The mu'adhdhin has a superiority of one hundred and twenty good deeds over all those who attend the prayer on hearing his adhan, and if he himself also gives the iqamah, he receives the reward of two hundred and forty good deeds, except for the one who says the same words as the mu'adhdhin (at the time of the adhan and iqamah) (for he too attains this reward and virtue)."
[Musnad al-Harith (Zawa'id al-Haythami): 249; its chain contains Abdullah bin Ziyad al-Ifriqi, a da'if (weak) narrator.]

It is narrated from Sayyiduna Abu al-Khayr (may Allah have mercy on him) that the Messenger of Allah (peace and blessings be upon him) said: "Those who give the adhan (the mu'adhdhins) will be the people with the longest necks (that is, the most distinguished and honoured) on the Day of Resurrection, and they will be the first people who are given permission to speak on the Day of Resurrection."
This narration is mursal, while Imam al-Tabarani narrated it in al-Mu'jam al-Awsat through Ibn Lahi'ah with the same chain from Abu al-Khayr, from Sayyiduna Uqbah bin Amir (may Allah be pleased with him), as mawsul (with a connected chain).

It is narrated from Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him) said: "Indeed, the inhabitants of the heaven (the angels) do not hear anything of the voices of the people of the earth except the adhan."
The narrator Ubaydullah bin al-Walid in its chain is extremely weak (da'if jiddan).

It is narrated from Sayyiduna Ubayy bin Ka'b (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "I was admitted into Paradise, and there I saw tall domes and dome-like palaces made of pearls. I asked: O Jibril, for whom are these? He said: These are for the mu'adhdhins and for the imams who carry out the duties of leading the prayer from your Ummah."
Imam Abu Ya'la's teacher, Muhammad bin Ibrahim al-Shami, is a severely weak narrator.

It is narrated from Imam al-Hasan al-Basri (may Allah have mercy on him) that he said: "It has reached us that the first of all people to be clothed in the garments of Paradise on the Day of Resurrection will be those who give the adhan (the mu'adhdhins)."
The chain of this narration contains Isma'il bin Muslim al-Makki, a da'if (weak) narrator; however, other sahih hadith and supporting reports regarding the virtue of the mu'adhdhins are found in the books of Sunan.