'Angel' in the Bible

Nebuchadnezzar made answer and said, Praise be to the God of Shadrach, Meshach, and Abed-nego, who has sent his angel and kept his servants safe who had faith in him, and who put the king's word on one side and gave up their bodies to the fire, so that they might not be servants or worshippers of any other god but their God.

My God has sent his angel to keep the lions' mouths shut, and they have done me no damage: because I was seen to be without sin before him; and further, before you, O King, I have done no wrong.

But the angel of the kingdom of Persia put himself against me for twenty-one days; but Michael, one of the chief angels, came to my help; and when I came he was still there with the angel of the kings of Persia.

But I am going back to make war with the angel of Persia, and when I am gone, the angel of Greece will come. And there is no one on my side against these, but Michael, your angel.

And at that time Michael will take up his place, the great angel, who is the supporter of the children of your people: and there will be a time of trouble, such as there never was from the time there was a nation even till that same time: and at that time your people will be kept safe, everyone who is recorded in the book.