﴿ وَلَمَّا بَلَغَ أَشُدَّهُۥٓ ءَاتَيْنَٰهُ حُكْمًۭا وَعِلْمًۭا ۚ وَكَذَٰلِكَ نَجْزِى ٱلْمُحْسِنِينَ ﴾

“And when he reached full manhood, We bestowed upon him the ability to judge [between right and wrong], as well as [innate] knowledge: for thus do We reward the doers of good.”

(And when he reached his prime) between 18 and 30 years old (We gave him wisdom and knowledge) understanding and prophethood. (Thus We reward the good) in speech and works, in knowledge and wisdom.