It was at the time that John was on Patmos,
that Caesar-worship was demanded. 96-98
A.D. not only marked the end of the era of
the apostles, but it marked the beginning
of emperor worship.
Roman citizens were to burn a bit of incense
on the altar of Caesar, and was given a
certificate that they had done so. Then they
were free to worship their own god.
Christians refused to burn the incense and
that made them outlaws.