'Really' in the Bible

I know the distress you are suffering and your poverty (but you are rich). I also know the slander against you by those who call themselves Jews and really are not, but are a synagogue of Satan.

for they are [actually] the spirits of demons, performing [miraculous] signs. And they go out to the kings of the entire inhabited earth, to gather them together for the war of the great day of God, the Almighty.