R.A. Coombes Book Summary, Installment #8
Chapter 11, Pages 140-143
Revelation 17 
Rev 17:9 And here [is] the mind which hath wisdom. The seven heads are seven mountains, on which the woman sitteth.
Here we have the 'woman' sitting upon the beast, which has seven heads and ten horns; the heads are seven mountains or continents of earth - seven giant land masses:
Seven Giant Land Masses
How do we know the seven heads are continents? Rule number one, two and three of Biblical interpretation: context, context and context! Well, it's not Rome because Rome has 7 hills but not mountains. The symbolism of the beast is that it represents all the world empires. The 'woman' has authority over all seven continents. This is something previous world empires never accomplished. Throughout history, only one, has such comprehensive influence and authority.
"there are seven kings: five are fallen, and one is, [and] the other is not yet come;
and when he comes, he must continue a short space. And the beast that was, and is not,
even he is the eighth, and is of the seven, and goeth into perdition." Rev 17:10-11
These verses speaks of past, present and future world empires. The distinction? The 'woman' is a democratic kingdom/nation and the others are dictatorial monarchies. [Rome, while claiming democracy, was in reality a continuing dictatorship as was Alexander the Great.]
Unchallenged Power - The entire picture of the woman and the beast has to do with control and domination. The beast is not in a dominant position in relation to the woman; her power goes unchallenged. Type of power? influence in economic and military matters. The symbolism of verbs:
The seven kings/empires relate to Israel's history of the past, the present as of 90 AD, and the future. We know that all prophecy is centered on Israel and how it directly or indirectly relates and impacts the nation of Israel.
Seventh Empire ??
The Eighth Empire? ... next time
 Rev 17: http://www.blueletterbible.org/search/translationResults.cfm?Criteria=frev+17&t=KJV
This is up to page 143 in the 250 page book
Salvation? Luke 13:3; Titus 2:13, Revelation 19:11
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