Phil mentions several possibilities. Here is another.
Later in the book, Daniel's ritual preparations for invoking angelic revelations include dietary restrictions. See 9:3 and 10:3. Chapter one emphasizes that Daniel only ate vegetables and drank water. Verse 17 specifies that his abilities included understanding visions and dreams. Is his diet meant to be a relevant factor? Maybe.
As a side note: 10:3 says that Daniel went for "three whole weeks" without eating delicacies or meat or drinking wine.
That implies he normally ate and drank those things. I thought he only ate vegetables and drank water. Did Daniel's king's-food-free diet go the way of all diets?
I have collected and commented on the previous posts in Phil's new series on the Book of Daniel here.
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