Michael = the only angel designated an archangel in the Bible (Jude 9). Another the other seven names given in Hebrew tradition is also Gaberiel. This war in heaven occurs upon the assension of Christ back into heaven and Satan losing his power over death and his access to the presence of God and also losing his miraculous powers. Note all the verses about Christ destroying Satan and seeing his powers curtailed, also Rev. 20, the chaining of Satan.