Show me where revival is in the bible. Revival is man made and usually is run by Satan off the will
and flesh of men.
What purpose would a Revival fulfill? A time to seek after a sign? A chance to be wicked and perverse?
To answer id say show me some new heretical wind of doctrine and id say that would be a true sign a false revival
is about to start. Satan just like God confirms his word with signs and wonders.
The only true things that have happened in church history is periods of repentance, with brokeness and moral reform.
The Holyspirit gave no warnings. It happens where and when He pleases.