'But the prince of the Persian kingdom resisted me twenty-one days.Then Michael, one of the chief-princes, came to help me, because I was detained there with the king of Persia (Daniel 10:13).'
Moses teaches us these things more distinctly: 'For when the Most High allocated the nations, as He scattered the sons of Adam, He appointed the boundaries of the nations according to the number of the angels.' And in the Holy Gospels our Lord says to the apostles, 'See that you do not despise one of my little ones, because their angels see the face of my Father in heaven' ...And blessed Daniel agrees with them for he speaks of the prince of the kingdom of Persians [and]...the prince of the kingdom of the Greeks, and calls the prince of Israel Michael.
Why then [does] the prince of the Persian kingdom seem to oppose the advocate of God's people? After all, it is clear to everyone that the nature of the angels is better than the passions by which we are gripped, and their nature is full of holiness. The fact that they unquestionably obey the wishes of God can be learned throughout Scripture. How then does the prince of the kingdom of the Persians seem to oppose the care of the Israelites? For the princes of the Persians and the Greeks, that is, those who have been entrusted the protection and care of these nations, in so much as they are fondly disposed towards those in their care and see the transgressions of Israel, were displeased to see the Israelites enjoying more consideration. They did not know the mystery that had been hidden in God, who made all things. After the incarnation of our Savior, as Paul says, 'The manifold wisdom of God was made known to the rulers and authorities through the church." Therefore, since they did not know this mystery and they saw God's great providence for Israel, those who had been entrusted with the care for the other nations were displeased to see that after the law, the prophets, and such teaching and care, the Israelites behaved worse and were inflamed by more evil than the nations who were shepherded by them.