Commentaries
6:1-5 We notice to the glory of God, that though Daniel was now very old, yet he was able for business, and had continued faithful to his religion. It is for the glory of God, when those who profess religion, conduct themselves so that their most watchful enemies may find no occasion for blaming them, save only in the matters of their God, in which they walk according to their consciences.
3. Daniel was preferred—probably because of his having so wonderfully foretold the fall of Babylon. Hence the very expression used by the queen mother on that occasion (Da 5:12) is here used, "because an excellent spirit was in him."
king thought to set him over the whole realm—Agreeing with Darius' character, weak and averse to business, which he preferred to delegate to favorites. God overruled this to the good both of Daniel, and, through him, of His people.