Revelation 17:9

Here is the mind that has wisdom: the seven heads are seven mountains, on which the woman sits.

Revelation 13:18

Here is wisdom. Let him that has understanding, count the number of the beast: for it is the number of a man, and his number is six hundred and sixty-six.

Revelation 17:3

And he carried me away in spirit into the wilderness; and I saw a woman sitting on a scarlet beast, that was full of impious names, and that had seven heads and ten horns.

Matthew 13:11

He answered, and said to them: Because it is given to you to know the mysteries of the kingdom of heaven; but to them it is not given.

Matthew 24:15

When, therefore, you see that detestable thing that makes desolate, spoken of by Daniel the prophet, standing in the holy place, (let him that reads understand;)

Revelation 13:1

{ And I stood on the sand of the sea, and saw a beast coming up out of the sea, and he had seven heads and ten horns, and on his horns ten diadems, and on his heads names impiously irreverent.}

Revelation 17:7

And the angel said to me: Why did you wonder? I will tell you the mystery of the woman, and of the beast that carries her, that has seven heads and ten horns.

Revelation 17:18

And the woman that you saw is that great city, which reigns over the kings of the earth.

Treasury of Scripture Knowledge

Summary

And here is the mind which hath wisdom. The seven heads are seven mountains, on which the woman sitteth.

Bible References

Here

Revelation 13:18
Here is wisdom. Let him that has understanding, count the number of the beast: for it is the number of a man, and his number is six hundred and sixty-six.
Matthew 13:11
He answered, and said to them: Because it is given to you to know the mysteries of the kingdom of heaven; but to them it is not given.
Matthew 24:15
When, therefore, you see that detestable thing that makes desolate, spoken of by Daniel the prophet, standing in the holy place, (let him that reads understand;)

The seven

Revelation 17:3
And he carried me away in spirit into the wilderness; and I saw a woman sitting on a scarlet beast, that was full of impious names, and that had seven heads and ten horns.
Revelation 13:1
{ And I stood on the sand of the sea, and saw a beast coming up out of the sea, and he had seven heads and ten horns, and on his horns ten diadems, and on his heads names impiously irreverent.}