In considering the identity of the armies of heaven,
the options are twofold: angels or (deceased) saints. The abundant references in Scripture to angelic hosts (e.g., 2 Kings 6:17; Matthew 26:53; Revelation 12:7) could make us think of angels. But other factors tip the balance in favour of understanding these armies as saints. Revelation 17:14 had listed saints as those “with him” at the battle. Further, in the book of Revelation the wearing of white garments characterizes saints (Revelation 3:4–5, Revelation 3:18; Revelation 4:4; Revelation 6:11; Revelation 7:9, Revelation 7:13–14—though note Revelation 15:6).
14 And the armies of heaven, arrayed in fine linen, white and pure, were following him on white horses.