Michael was the angel who protected Israel (see Daniel 10:13, 21; Revelation 2:1, 8, 12).
the book: This might be the Book of Truth (Daniel 10:21; see 7:10).
will be delivered: All past rescues of God's people in Daniel (for example, Daniel 3:28; 6:27) hinted at and now lead to the resurrection from the dead (12:2–3).