This excerpt is taken from the book published by Maktabah Darussalam's Department of Authorship and Compilation Dictionary of Names and Rulings and Issues of Newborns.
Our pure Shariah has informed us of certain rulings at the time of a child's birth, one of which is to say the Adhan in the child's right ear immediately after birth.
Hazrat Abu Rafi’ (may Allah be pleased with him) said:
رأيت رسول الله صلى الله عليه وسلم أذن فى أذن الحسن بن علي، حين ولدته فاطمة، بالصلاة
“When Hazrat Fatimah (may Allah be pleased with her) gave birth to Hasan bin Ali (may Allah be pleased with them both), I saw the Messenger of Allah (peace and blessings be upon him) say the Adhan of prayer in his ear.”
Reference: Sunan Abi Dawood, Adab, Chapter on the newborn being given Adhan in his ear, Hadith: 5105 and Jami’ at-Tirmidhi, Al-Adha, Chapter on Adhan in the ear of the newborn, Hadith: 1514. The hadith is weak; it was declared weak by Shaykh Al-Albani in Hidayat al-Ruwat: 138/4 and Fawaz Ahmad Zumrali in Takhrij Tuhfat al-Mawlood, p. 53 and Husain Saleem Asad in Tahqiq Musnad Abi Ya’la: 151/12.
[Although this narration is weak, it has been a continuous practice from the beginning. Imam Tirmidhi (may Allah have mercy on him) after mentioning this narration says: و العمل عليه and this narration is acted upon. For this reason, some scholars have deemed it permissible to say only the Adhan in the child's ear.] And Allah knows best. (Nasir)
✿ Wisdoms of Saying the Adhan:
Several wisdoms of calling the Adhan are mentioned, of which we briefly mention a few.
➊ One benefit of calling the Adhan at the time of birth is that the very first sound that enters a person's ears is that exalted and high-ranking voice which declares the greatness and grandeur of the Lord of the Worlds and mentions the testimony by which a person enters Islam. It is as if, upon entering the world, the person is reminded that these are the fundamental laws of Islam. Similarly, when a person is about to depart from this world, the Kalima of Tawheed is taught to him at the time of death, as the Noble Prophet ﷺ said:
لقنوا موتاكم لا إلٰه إلا الله
“Teach the dying people near you to say La ilaha illallah.”
Reference: Sahih Muslim, Al-Jana'iz, Chapter on Teaching the Dying La ilaha illallah, Hadith: 916 and Sunan Abi Dawood, Al-Jana'iz, Chapter on Teaching, Hadith: 3117
Certainly, considering the power of Allah, it is not far-fetched to believe that the effect of the Adhan passes through the child's ears to his heart, and the child is influenced by this teaching, even though outwardly no one may notice.
➋ Upon hearing the words of the Adhan, Satan flees far away.
Reference: Sahih al-Bukhari, Beginning of Creation, Chapter on the Description of Iblis and his soldiers, Hadith: 5823
Since Satan also lies in wait at the time of a child's birth, as soon as he hears the voice of the Adhan, his influence will diminish, obstacles will be placed in his initial relations with the child, and Satan will return frustrated and unsuccessful, writhing in anger.➌ This world is a place of trial, so upon arrival, the child is first taught about Allah, the religion of Islam, and divine worship, and before Satan's invitation reaches him, he is invited by the Most Merciful. A servant begins with a pure nature (Fitrah), meaning that when he is born, according to Islam, he has life and is among the Muslims, but after birth, Satan tries to cause change and alteration in his nature to distance him from Islam and remove him from the pure nature.
Reference: Tuhfat al-Mawdud: 54
The benefits and wisdoms explained by Imam Ibn Qayyim (may Allah have mercy on him) are a great proof that from the predecessors to the successors, all scholars have taken great care to invite to faith along with the belief in Tawheed. To block Satan's invitation and to prevent indulgence in desires, such tireless efforts are made that these teachings are instilled in a person's ears at the very moment he begins to enjoy the gentle breeze of his worldly existence.