The demon argued his right to stay in the man.
But Jesus said, “Come out the man, thou unclean
spirit”.

Jesus showed that the demon had to leave. But
He noticed that there were many others present
also. So Jesus demanded that they give their
names and how many were there.

The first one said, “My name is Legion: for we
are many.” The name ‘legion’ means many or
a great number. Jesus wanted the whole lot of
them to be cast out.

Often when several demons are cast out there
are others hiding in the person not wanting to be
detected or even pretending to leave. Later it
will show that the person was not completely
delivered.