"Our text reveals two significant truths. First, the battle of Armageddon is fought for the destruction of Babylon. Second, in this battle the Lord comes upon Babylon as a thief. He comes in a spiritual visitation of judgment to strip and purge from His people in Babylon the death of the carnal mind; those outer, earthly things they cherish above the spirit and truth and glory of Christ. That is what a thief does -- he plunders the house, carrying off those things treasured by the householder! He appears as a thief in the night, and there have often been times in the lives of all of God's called and chosen elect when He has stolen out of the dark hour of our ignorance some carnal concept, some religious tradition, some perverted doctrine, some Babylonish garment of exquisite design that we have hidden in our tent of experience. Ah, we must stay awake to joyfully receive Him in His coming to us, His appearing in us; if we fail to do so He will come like a thief, He will come into our world uninvited and unannounced, He will overtake us unexpectedly and break up our life style and smash our religious games, exposing our pretense. Those who are awake to reality do not have their houses plundered. These willingly yield up the things they once prized, which now are counted but dung that they might win Christ."

Much more in the text:

https://www.godfire.net/eby/rev187.html