But the prince of the kingdom of Persia withstood me one and twenty days: but, lo, Michael, one of the chief princes, came to help me; and I remained there with the kings of Persia.
But the prince of ... Persia withstood me - the angel of darkness that represented the Persian world-power, to which Israel was then subject, withstood the angel who was coming to relieve Daniel, as the representative of God's people Israel. This verse gives the reason why, though Daniel's "words were heard from the first day" (Daniel 10:12), the good angel did not come to him until more than three weeks had elapsed (Daniel 10:4).
One and twenty days - answering to the "three full weeks" of Daniel's mourning (Daniel 10:2).
But, lo, Michael, one of the chief princes - i:e., "Michael," 'Who is like God?' Though an archangel, and "one of the chief princes," Michael was not to be compared to God.
Came to help me - Michael, as patron of Israel before God Daniel 10:21; (Daniel 12:1), "helped" to influence the Persian king to permit the Jews' return to Jerusalem.
And I remained there - I was detained there with the kings of Persia - i:e., with the angel of the Persian rulers, with whom I had to contend, and from whom I should not have gotten free but for the help of Michael. Gesenius translates х nowtartiy (H3498), from yaatar (H3498)], 'I obtained the ascendancy' - i:e., I gained my point against the adverse angel of Persia, so as to influence the Persian authorities to favour Israel's restoration. The Hebrew admits of this rendering, as well as that of the English version, and the sense decidedly favours it.