'Young' in the Bible

They were to be young men without physical defect, handsome in appearance, skilled in all wisdom, quick to learn, prudent in how they used knowledge, and capable of serving in the king's palace. They were to learn the literature and language of the Chaldeans.

The chief officer told Daniel, "I fear his majesty the king, who has determined what you eat and drink. If he notices that your faces are more pale than the other young men in your group, I will forfeit my head to the king."

Then compare how we look with the young men who ate the king's rich food, and treat your servants in accordance with what you observe."

At the end of ten days their appearance was better and their faces were well-nourished compared to the young men who ate the king's rich food.

As for these four young men, God gave them knowledge, aptitude for learning, and wisdom. Daniel also could understand all kinds of visions and dreams.