In the context of the Book of Daniel, Daniel distinguished himself in service to King Darius due to his exceptional qualities and faithful conduct. The text in Daniel 6:3-4 (RSV) states:
3 Then this Daniel became distinguished above all the other presidents and satraps, because an excellent spirit was in him; and the king planned to set him over the whole kingdom. 4 Then the presidents and the satraps sought to find a ground for complaint against Daniel with regard to the kingdom; but they could find no ground for complaint or any fault, because he was faithful, and no error or fault was found in him.
Daniel's integrity and excellence in his work led to his promotion, but this also aroused jealousy among his colleagues. The satraps, feeling envious of Daniel's success and the king's favour toward him, sought ways to bring charges against him. Despite their efforts, they could find no legitimate grounds for accusations because of Daniel's faithfulness and lack of wrongdoing.