A look into the sequence of timelines found in Revelation and
verified by texts found in the book of Daniel is a very interesting
study. There are some timelines that have a distinct start and
finish date that history provides the proof for. One of these is the
prophecy in Daniel 8:14. "And he said unto me, unto two
thousand and three hundred days; then shall the sanctuary be
cleansed."
First we need to consider what a day in prophecy represents
using the Bible as the rule; it's called the day/year principal and is
supported in two scriptures. "After the number of the days in
which ye searched the land, even forty days, each day for a year,
shall ye bear your iniquities, even forty years, and ye shall know
my breach of promise" (Numbers 14:34). "And when thou hast
accomplished them, lie again on thy right side, and thou shalt
bear the iniquity of the house of Judah forty days: I have
appointed thee each day for a year" (Ezekiel 4:6).