Wa-itha balagha al-atfalu minkumu alhuluma falyasta'thinoo kama ista'thana allatheena min qablihim kathalika (surah An Nur: 59)

Tafseer Tafheem-ul-Quran by Syed Abu-al-A'la Maududi

(24:59) And when your children have grown sex conscious, *91 they should receive your permission for this just as their elders get permission. In this way Allah makes His Revelations plain to you for He is All-Knowing, AllWise.

Wa izaa balaghal atfaalu minkumul huluma fal yastaazinoo kamas taazanal lazeena min qablihim; kazaalika yubaiyinul laahu lakum Aayaatih; wallaahu `Aleemun Hakeem

*91) That is, when they have reached the age of puberty. As has been explained in E.N. 87 above, the signs of puberty in the case of boys and girls are nocturnal emission and menstrual discharge respectively. There is, however, a difference of opinion among the jurists regarding the beginning of puberty in those boys and girls who for some reason do not show these physical signs for an unduly long time. According to Imam Shafi`i, Imam Abu Yusuf, Imam Muhammad and Imam Ahmad, a boy or a girl of IS years will be considered to have attained puberty, and a saying of Imam Abu Hanifah also supports this view. But the wellknown view of Imam Abu Hanifah is that in such cases the age of puberty will be 17 years for girls and 18 years for boys. Both these opinions are the result of juristic reasoning and neither is based on any injunction of the Qur'an or Sunnah. It is therefore not necessary that the age limits of 15 or 18 years be accepted as marking the beginning of puberty everywhere in the world in abnormal cases. In different countries and ages there are different conditions of physical development and growth. The age of puberty in a certain country can be determined by means of the law of averages in normal cases. As for abnormal cases, the mean difference of ages may be added to the upper age limit to determine the age of puberty. For instance, if in a country, the minimum and maximum ages for noctural discharge are normally 12 and 15 years respectively, the mean difference of one and a half years may be added to the maximum limit of 15 years to determine the beginning of puberty for abnormal cases. The same principle can be used by the legal experts of various countries to fix the age of puberty keeping in view their peculiar local conditions.
There is a tradition quoted from Ibn `Umar in support of the age of 15 years for puberty. He says: "I was 14, when I presented myself before the Holy Prophet to ask his permission to join the Battle of Uhud, but he declined permission. Then on the occasion of the Battle of the Trench, when I was 15, I was again presented and he permitted me to join." (Sihah Sitta, Musnad Ahmad). This tradition, however, does not stand scrutiny for the following two reasons:
(a) The Battle of Uhud took place in Shawwal, 3 A.H., and the Battle of the Trench in Shawwal, 5 A.H. according to Ibn Ishaq, and in Zil-Qa`d, 5 A.H. according to Ibn Sa`d. There is an interval of two years or more between the two events. Now if Ibn `Umar was 14 at the time of the Battle of Uhud, he could not be 15 at the time of the Battle of the Trench. It thay be that he mentioned 14 years for 13 years and 11 months and 15 years for 15 years and 11 months.
(b) It is a different thing to be regarded as an adult for the purposes of war and quite different to be legally adult for social affairs. They are not necessarily interconnected. Therefor the correct view is that the age of 15 for an abnormal boy has been fixed on the basis of analogous and juristic reasoning and not on the basis of anything in the Qur'an or Sunnah.