Tirmidhi

Explanation:
1:
When a boy or girl reaches the age of fifteen years according to the Hijri calendar, they attain the age of puberty. Likewise, the appearance of pubic hair and the occurrence of a wet dream (ihtilam) are also among the signs of puberty. For a girl, the onset of menstruation (hayd) is also a sign of puberty.

Hadith Commentary:
It is understood that at the age of fifteen years, a male is considered to have reached puberty, and all the legal (shar‘i) rulings are fully applicable to him.

Hadith Commentary:
➊
This hadith shows that there was a one-year gap between the Battle of Uhud and the Battle of Khandaq, because at the time of the Battle of Uhud, Abdullah ibn Umar (radi Allahu anhu) was fourteen years old, and by the Battle of Khandaq, he had turned fifteen.

➋
In fact, Imam al-Bukhari (rahimahullah) has presented this hadith in support of Musa ibn Uqbah’s opinion that the Battle of Khandaq took place in the fourth year of Hijrah, because it is certain that the Battle of Uhud occurred in the third year of Hijrah, and if the Battle of Khandaq happened one year later, then it clearly means it took place in the fourth year of Hijrah. However, other biographers of the Prophet say that the Battle of Khandaq occurred in the fifth year of Hijrah, because at the time of the Battle of Uhud, Abu Sufyan had said that the next year there would be a battle again at Badr. But due to famine in Makkah, they could not prepare, so they did not come that year, i.e., in the fourth year of Hijrah, whereas the Prophet (sallallahu alayhi wa sallam) did go towards Badr in the fourth year of Hijrah. However, since Abu Sufyan and the other polytheists of Makkah did not come, the Prophet (sallallahu alayhi wa sallam) returned to Madinah. After that, in the following year, i.e., the fifth year of Hijrah, Abu Sufyan, along with various tribes and the Jews of Madinah, attacked Madinah.

➌
The answer to the hadith presented by Abdullah ibn Umar (radi Allahu anhu) is that at the time of the Battle of Uhud, his fourteenth year had begun, and at the Battle of Khandaq, his fifteenth year was ending. In this way, it is not impossible for there to be a two-year period between the two battles.

Therefore, according to the generally accepted and reliable opinion, the Battle of Khandaq took place in the fifth year of Hijrah.

(Fath al-Bari: 7/491)
And Allah knows best.

Hadith Commentary:
It is understood that upon reaching the age of fifteen years, the child becomes subject to the rulings of Shari‘ah, and at this age, he can be considered eligible to bear witness.

Hadith Commentary:
(1)
According to this hadith, when a child reaches the age of fifteen years, the rulings applicable to adults are enforced upon him.
At this age, acts of worship, legal punishments (hudud), and other rulings of the Shariah will also become obligatory for him.
At this age, he will be able to participate in battle and will be entitled to a share of the spoils of war (ghanima).
If he is a belligerent disbeliever (harbi kafir), he will be killed.
At this age, his testimony will also be accepted.
If he experiences a wet dream (ihtilam) before this age, then the rulings of adulthood (bulugh) will be enforced from that point.
(2)
By "ihtilam" is meant the emission of seminal fluid that spurts forth, whether due to intercourse or in a state of sleep.
For women, the onset of menstruation (hayd) is a sign of their reaching adulthood (bulugh).
There is no fixed age limit for this.
The age may vary depending on health and regional factors.

Benefits and Issues:
➊
A child is considered to have reached puberty at the age of fifteen years.
And becomes legally responsible (mukallaf) for religious obligations.
Therefore, he can also be included in battle and fighting.
Before this, it is not permissible to take him to war.

➋
And when he participates in battle,
he will receive an official share from the spoils of war (ghanimah).

➌
If, before the age of fifteen or before the signs of puberty, he commits a crime, then the prescribed legal punishment (hadd) will not be applied to him.
He will be subject to disciplinary action and admonition (ta’zir wa ta’dib).
Similarly, any divorce (talaq) he pronounces will not be effective.
In legal decisions, the participation of his guardian (wali) will be necessary, and he will only obtain the right to dispose of his wealth independently and officially after this.

Benefits and Issues:
For someone to be considered legally (shar‘an) mature, the age of fifteen years is taken into account, whether or not pubic hair has appeared or whether or not nocturnal emission (ihtilam) has occurred. It is not permissible to include a minor in combat.

In official documents, a boy of fifteen years will be recorded as an adult, and anyone younger than that will be recorded as a minor, because the government maintains records of age and related matters. As for the other two signs, there is room for manipulation in them, even though they are definitive signs.

Benefits and Issues:

➊ From this hadith, scholars have deduced that the age of fifteen years is the age of maturity (bulugh), therefore a child of this age should be considered mature (baligh).

➋ In normal circumstances, reliance is placed on other signs of maturity, such as: the appearance of pubic hair, experiencing a wet dream (ihtilam), or the commencement of the monthly cycle (menstruation) in girls. However, if these signs do not appear in a boy or girl at the appropriate age, then upon completion of fifteen years of age, they can be declared mature (baligh).

Takhrij:
«أخرجه البخاري، الشهادات، باب بلوغ الصبيان وشهادتهم، حديث:2664، ومسلم، الإمارة، باب بيان سن البلوغ، حديث:1868، والبيهقي:3 /83.»©Explanation:
➊ According to this hadith, the age of legal capacity for transactions begins at fifteen years, which has been deemed acceptable and acknowledged.
➋ The author has also cited this hadith in this chapter precisely to clarify at what age buying and selling becomes valid.
Thus, a child under fifteen is considered a minor, while a youth of fifteen years is regarded as being under the ruling of men.
➌ From this hadith, observe the enthusiasm of the youth for jihad: he steps forward and presents himself for the service of jihad.
After failing the first time, he tries his luck again the following year and succeeds in his determination and resolve.
➍ It is understood from this that those younger than this age should not be recruited into the army.
➎ From this, the principle is also derived that a physical test should first be conducted for army recruitment; if found unsuitable, the candidate should be sent back.