1 Corinthians 10:20 “But the things which the heathens sacrifice, they sacrifice to devils, and not to God. And I would not that you should be made partakers with devils.”
This as an example of an Eastern Saint, Patriarch of Constantinople, and Doctor of the Church saying that even monotheistic people who don’t accept Christ don’t worship God the Father and have lost the hope of salvation:
Jeremiah said: “Your house has become for me the den of a hyena”. He does not simply say “of wild beast”, but “of a filthy wild beast”, and again: “I have abandoned my house, I have cast off my inheritance”.
But when God forsakes a people, what hope of salvation is left? When God forsakes a place, that place becomes the dwelling of demons.
…
“If you were to know my Father, you would also know me. But you neither know me nor do you know my Father”. Could I produce a witness more trustworthy than the Son of God? …if they thrust off the help of the Spirit, who should not make bold to declare plainly that the synagogue is a dwelling of demons?
God is not worshipped there. Heaven forbid! From now on it remains a place of idolatry. But still some people pay it honor as a holy place.
- St John Chrysostom, Adversus Judaeos, Homily 1
The “…” occurs a lot in this quote in order to cut out stuff that might be interpreted as overtly anti-semitic. I don’t know that CAF would want the whole thing quoted here.