The religious system in the first half of the tribulation began
from before the rapture.
It exists today - you may be part of it.
The left behind churches and pseudo christians become members
of the religious system identified as
the woman who rides the beast - also known as
the great whore.
...
Revelation 17:5
And on her forehead a name was written, a mystery, BABYLON THE
GREAT, THE MOTHER OF
HARLOTS AND OF THE ABOMINATIONS OF THE EARTH.
...............................................................................
She ( the harlot ) is destroyed at the mid-point of the 7 years - this allows the beast to
set up his own image and
mandate the worship of him and his image.
The great whore and the beast are both empowered by satan - when satan determines
that the whore is no longer useful - he destroys her and consolidates his power under
the beast and the false prophet.

[ the defilement of Jerusalem by the beast last half of tribulation ]
or
[ back to the index for the chronology of The Book of Revelation ]