The beast that was, and now is not, is an eighth king, who belongs to the other seven and is going into destruction.
Here we have the mystery of this vision explained. The apostle wonders at the sight of this woman: the angel undertakes to open this vision to him, it being the key of the former visions; and he tells the apostle what was meant by the beast on which the woman sat; but it is so explained as still to need further explanation. 1.
Commenting on Revelation 17:7-13
And the beast that was, and is not, even he is the eighth,.... That was in embryo in John's time, and yet was not come to its power and grandeur, is the eighth king; and this is the Papacy, which takes the name of the beast, because it is the head of the beast, and the only surviving head of the beast, or Roman empire...
Verse 11. And the beast that was, and is not. That is, the one power that was formerly mighty; that died away so that it might be said to be extinct; and yet () that "still is," or has a prolonged existence.