Is the prayer valid if an adult follows a minor (child) in an obligatory prayer (Fard)?
Chapter on Imamate and Congregational Prayer
Al-Mughni
Book of Prayer
Primary text
The prayer is not valid if an adult follows a minor in an obligatory prayer. This view is held by Ahmad, Ibn Mas'ud, Ibn Abbas, 'Ata', Mujahid, Sha'bi, Malik, Thawri, Awza'i, and Abu Hanifa. The justification is that leadership in prayer ('Imamah') is a state requiring completeness, and a minor is not considered complete, thus being similar to a woman leading men. Furthermore, there is a concern that a minor might violate a condition of prayer or recitation during silent parts.
Supporting text
The opposing view, which permits this structure, is held by Al-Hasan, Al-Shafi'i, Ishaq, and Ibn Al-Mundhir. They argue based on the generality of the saying, "The one who knows the Book of Allah best shall lead you," and the hadith of 'Amr ibn Salamah Al-Jarmi, where the Prophet (peace be upon him) instructed his people that the one who knows the Quran best should lead them, and 'Amr stated he led them while being seven or eight years old. This supporting opinion is also consistent with the permissibility of a person praying a supererogatory prayer ('Mutanaffil') leading those praying an obligatory prayer ('Muftarid').