'Book of Daniel'
Dan 1:3-4 Then the king instructed Ashpenaz, the master of his eunuchs, to bring some of the children of Israel and some of the king's descendants and some of the nobles, young men in whom there was no blemish, but good-looking, gifted in all wisdom, possessing knowledge and quick to understand, who had ability to serve in the king's palace, and whom they might teach the language and literature of the Chaldeans.
All Jewish youths were supposed to be educated and knowledgeable in the laws of God for every parent is mandated to teach their children. In fact, Jewish children are supposed to memorise and to understand Moses' laws.
Then how come that so few youths were saved?
Deu 11:18-19 "Therefore you shall lay up these words of mine in your heart and in your soul, and bind them as a sign on your hand, and they shall be as frontlets between your eyes. You shall teach them to your children, speaking of them when you sit in your house, when you walk by the way, when you lie down, and when you rise up."
Rejecting God's Will
Jer 35:15 "I have also sent to you all My servants the prophets, rising up early and sending them, saying, 'Turn now everyone from his evil way, amend your doings, and do not go after other gods to serve them; then you will dwell in the land which I have given you and your fathers.' But you have not inclined your ear, nor obeyed Me.
Since Israel refused to obey the word of God and to repent of their evil ways, the Israelites would not teach their children the word of God, which they had rejected. Without the word of God and the truth, these youths could not believe that it was God's will for Jerusalem to be conquered by the Babylonians.
Jer 27:14-15, 17 "Therefore do not listen to the words of the prophets who speak to you, saying, 'You shall not serve the king of Babylon,' for they prophesy a lie to you; for I have not sent them," says the LORD, "yet they prophesy a lie in My name, that I may drive you out, and that you may perish, you and the prophets who prophesy to you... 'Do not listen to them; serve the king of Babylon, and live! Why should this city be laid waste?"
All those who believed the false prophets promising victories, peace and God's deliverance were all killed trying to fight off the enemies.
Simirlarly, Christians who cannot believe that it is God's will that Jerusalem, US, UK and EU (former Christian nations) will be destroyed by Iran in the coming World War 3, will not teach nor talk about this truth. They would rather embrace lies and false prophecies of peace, blessings and prosperity.
Submitting to God's Will
Dan 9:2 in the first year of his reign I, Daniel, understood by the books the number of the years specified by the word of the LORD through Jeremiah the prophet, that He would accomplish seventy years in the desolations of Jerusalem.
Knowing that it was God's will for them to serve the Babylonians for seventy years, these Jewish youths had decided to live in peace and serve the Babylonians faithfully as though they were serving God. Because of their peace and faithfulness, they were treated more favourably than those from other nations.
Jer 29:6-7 Take wives and beget sons and daughters; and take wives for your sons and give your daughters to husbands, so that they may bear sons and daughters -- that you may be increased there, and not diminished. And seek the peace of the city where I have caused you to be carried away captive, and pray to the LORD for it; for in its peace you will have peace."