Extracts and comments from Revelation Chp. 12:7
And there came to be (a)war in the Heaven: (b)Michael and his angels going forth to war with the (c)dragon; who resisted with his angels.
(a) "War in the Heaven"; this Scripturally clearly is a first occurrence, and the force used is described as "war", to convey to human minds the meaning.
(b) "Michael"; is the special angel (archangel) of the Jews, (Dan. 10:13-21), and as such is championing the Jewish cause on behalf of Jehovah.
(c) "Dragon"; i.e. Satan and his angels.