Also some notes on Revelation chapter 9 so that we get a better idea:
Rev. 9:1 And the fifth angel blew his trumpet, and I saw a star fallen from heaven to earth, and he was given the key of the shaft of the bottomless pit;
Rev. 9:2 he opened the shaft of the bottomless pit, and from the shaft rose smoke like the smoke of a great furnace, and the sun and the air were darkened with the smoke from the shaft.
Rev. 9:3 Then from the smoke came locusts on the earth, and they were given power like the power of scorpions of the earth;
Rev. 9:4 they were told not to harm the grass of the earth or any green growth or any tree, but only those of mankind who have not the seal of God upon their foreheads;
Rev. 9:5 they were allowed to torture them for five months, but not to kill them, and their torture was like the torture of a scorpion, when it stings a man.
Rev. 9:6 And in those days men will seek death and will not find it; they will long to die, and death will fly from them.
Rev. 9:7 In appearance the locusts were like horses arrayed for battle; on their heads were what looked like crowns of gold; their faces were like human faces.
Star is the Devil; Abyss is the depth of the human heart; Earth is our flesh. So the devil has been given access to our heart to darkened our mind (sun) and thoughts (air) with evil thoughts (smoke), "For out of the heart come evil thoughts, murder, adultery, fornication, theft, false witness, slander" (Mt. 15:19). Great furnace, understand to mean the passionate (fiery) desires of the flesh, which the demons (locusts) provoke in us in order to lead us to sin. They are likened to locusts because they eat the grass of the earth, that is the good thoughts, which sprout forth when we read scripture (plant seeds). They also eat every green growth, that is every good deed, and every tree, signifying those established in virtue but who have not sealed their mind (forehead) with the orthodox faith and the unceasing invocation of the Jesus Prayer.
The Five months represent the sensible world because of the five senses, which the demons make use to lead us into sin if we choose what is transient (money, pleasures, etc), instead of what is eternal, "For all that is in the world, the lust of the flesh and the lust of the eyes and the pride of life, is not of the Father but is of the world" (1 John. 2:16).
Btw, seven year tribulation is the anguish of the soul, which, on account of its laxity in performing the commandments or total unbelief has become a house of the seven spirits, that is of the seven principal passions or vices, "When the unclean spirit has gone out of a man, he passes through waterless places seeking rest, but he finds none. Then he says, `I will return to my house from which I came.' And when he comes he finds it empty, swept, and put in order. Then he goes and brings with him seven other spirits more evil than himself, and they enter and dwell there; and the last state of that man becomes worse than the first. So shall it be also with this evil generation" (Mt. 12:43-45). All of us are subject to this tribulation, which we are called to suffer willingly, yet not give in. It is also called seven year tribulation, to mean, that it is experienced only in this age - for present time is seven-fold (weekly) - whereas in the age to come there will be no sorrow or anything of that sort, but only unspeakable joy in the eternal presence of God.
Horses ready for battle signify the exciting aspect (desiring) of the soul, - those who know horse physiology will understand the link; crowns of gold stand for the passion of greed, that is, love for money and human faces the passion of vainglory, men's praise. This alludes to the three temptations of Christ, which all of us are called to face.
... and so on ...
"He who endures to the end and does not give into sin will be saved."