18:9 “When the kings of the earth who committed adultery with her and shared her luxury see the smoke of her burning, they will weep and mourn over her.
“When the kings of the earth
Here the expression, 'the KINGS of the EARTH', denotes leadership of religious organizations (see verse 3). It is broader than the seven kings noted in Revelation 17:9-10. In a way this is how riches/wealth are denoted (James 5:1-6).
The religious leadership by this time has become so entwined with economic needs to keep their churches, synagogues, and mosques going that they have ignored how God can supply every need. For protestant denominations, in particular, the leadership has become very good at "marketing" religious programs that are tailored to every age group. Sadly, the inner spiritual needs of the attendees often go unmet.
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Let's stay with the symbolic view for a moment. It seems implausible that religious leadership would have difficulty with IMMORALITY (including the term 'acts' which gives this a strong sexual overtone), but when we consider how often religious leaders had difficulties in the past (for example, 2 Samuel 11) and in recent times the reported relationships of various religious leaders (both Protestant and Catholic), this verse is confirmed. Having done these acts, unless they repented, they are included in the list in Revelation 21:8.
Webster's dictionary defines SENSUOUSLY as "producing or characterizing by gratification of the senses". From a symbolic viewpoint, a person must ask whether the church has SENSUALIZED its appeal. This way of trying to help God perform His work isn't what John 3:16-21 is all about. Furthermore, things of God are not visual (one of the senses) (Hebrews 11:1-3) or they tasted something different (Hebrews 6:1-5-8).
see the smoke of her burning, they will WEEP and MOURN over her.
This is the Revelation way of saying what Jesus said in Matthew 13:36-43, Matthew 24:45-51, Matthew 25:14-30, and Luke 13:22-30. A person can only wonder how much of this "darkness" has invaded the church? This is a FOREVER BURNING (Revelation 19:3); hence, this must be SPIRITUAL and not PHYSICAL in nature. This is consistent with the view that the bowl judgments are almost exclusively spiritual in form.