Therefore shall her plagues come in one day,
death, and mourning, and famine;
and she shall be utterly burned with fire:
Revelation 18:8
Some wonder how long the 7 plagues of the last days will last. No one knows, but Scripture gives us a possible hint. When it says "in a day", and since a day = a year in prophecy, it seems logical within a day means less than 12 months.
