Even though the young men were torn from their homes and families and given new identities by a foreign king, they did not become bitter and turn their backs of God.
They were determined to continue to live their religion as best they could. For these Hebrew young men, part of that religion included a dietary code that forbade certain foods found on the king’s table. They decided to eat only grains, vegetables, and fruit, and to drink only water since those were permitted under Mosaic Law. They could eat meat, but only certain animals killed under specific conditions.
The Prince over the eunuchs was concerned that the boys would not thrive under such a diet, but he agreed to a ten day trial. Using their eating plan, Daniel and his friends flourished. Not only did they look healthy and well nourished, but according to Josephus, they did not develop the effeminate bodies and countenances of the other boys who had also been made eunuchs.
This was a wonderful witness to those at Nebuchadnezzar’s court regarding the great power of the God of Israel.
(Josephus – Complete Works., Translated by William Whiston, Kregel Publications, Grand Rapids, Michigan, 1960., pgs 222-223)