For their power is in their mouth,.... In what proceeded out of their mouth, or seethed to do so; in their guns, and what came out of them: and in their tails; which may design their foot soldiers, which were as the tail to their horse, and who sometimes did great service; or their way of fighting when they fled, by casting up arrows into the air, which would fall upon the heads and horses of those that pursued them; or their ambushments, by which they destroyed many; or their perfidious violation of treaties; or it may be their tails may intend the doctrine of Mahomet, the false prophet, who is the tail, Isa 9:15, for their tails were like unto serpents; crooked, crafty, poisonous, and, pernicious: and had heads; every tail had a head to it; which may be understood of the officers of the foot soldiers, or of the priests and teachers of the Mahometan religion: and with them they do hurt; with their guns, the power in their mouth, they did hurt to the bodies of men; and with their false doctrines, their tails, they did hurt to the souls of men; the Ethiopic version here adds, "five months"; which seems to be taken from Rev 9:10.