حَدَّثَنَا مُحَمَّدُ بْنُ الْوَزِيرِ الْوَاسِطِيُّ، حَدَّثَنَا إِسْحَاقُ بْنُ يُوسُفَ الأَزْرَقُ، عَنْ سُفْيَانَ، عَنْ عُبَيْدِ اللَّهِ بْنِ عُمَرَ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، قَالَ عُرِضْتُ عَلَى رَسُولِ اللَّهِ صلى الله عليه وسلم فِي جَيْشٍ وَأَنَا ابْنُ أَرْبَعَ عَشَرَةَ فَلَمْ يَقْبَلْنِي ثُمَّ عُرِضْتُ عَلَيْهِ مِنْ قَابِلٍ فِي جَيْشٍ وَأَنَا ابْنُ خَمْسَ عَشَرَةَ فَقَبِلَنِي . قَالَ نَافِعٌ فَحَدَّثْتُ بِهَذَا الْحَدِيثِ عُمَرَ بْنَ عَبْدِ الْعَزِيزِ فَقَالَ هَذَا حَدُّ مَا بَيْنَ الصَّغِيرِ وَالْكَبِيرِ . ثُمَّ كَتَبَ أَنْ يُفْرَضَ لِمَنْ بَلَغَ الْخَمْسَ عَشَرَةَ .
That Ibn 'Umar said: "I was reviewed before army, and I was fourteen years old, but he did not accept me. Then I was reviewed before him later in army while I was fifteen years old, and he accepted me." Nafi said: "I narrated this Hadith to 'Umar bin 'Abdul-'Aziz and he said: 'This is the limit that distinguishes between youth and manhood.' The he wrote to give salaries to whoever reached fifteen years of age.
Source: Jami` at-Tirmidhi — repository translation · Imam Abu Isa Muhammad ibn Isa al-Tirmidhi — authenticity/grade metadata requires independent source review · Sunnah.comAudio not available for the selected reciter.
Source: Jami` at-Tirmidhi — repository arabic · Imam Abu Isa Muhammad ibn Isa al-Tirmidhi · Sunnah.com