And the glory of the God of Israel was gone up from the cherub, whereupon he was, to the threshold of the house. And he called to the man clothed with linen, which had the writer's inkhorn by his side...
Ezekiel 9:3
"In the final conflict, relative to which the third angel utters his dreadful warning, but two classes are seen.
--One class keep the commandments of God, are marked with the seal of the living God, Eze. 9:2-6; Rev. 7:1-3; 14:1 and are seen on Mount Zion with the Lamb. 
--The other class receive the mark of the beast and image, and experience the wrath of God.
-One class are the worshipers of God, for they honor him by keeping his commandments.
-The other class receive the mark [a prominent religious institution and requirement] of the beast, therefore, are the worshipers of the beast, for they honor his institution.
We therefore conclude, that the observance of some institution of Papacy, (which is yet to be enforced by the two-horned beast,) --that stands opposed to the commandments of God,
-- constitutes the worship of the beast and his image."
James White