Recent personal experiences have made a close relative question their Christian beliefs to a far extent. They still believe in the possibility of an all-knowing God but question specific characteristics of Protestant-Christianity such as Priesthood. They strongly believe every Christian should have equal and direct access to God, preferring to align towards agnosticism. From the perspective of protestant-catholicism (Anglicanism) can this individual be said to be an unbeliever?

Is acting as if God exist while not actually believing that God exists is functionally identical or is that a sacrilege? To rephrase: is it feasible/possible/morally right to stick one finger in to test the waters or you accept Christianity in it's entirety and there is no middle ground? The reason I'm asking is that from the agnostic fence I've been sitting for the last 20-30 years of my life it seems that the satanic crowd have become increasingly active in the last decade or so and I want to have nothing in common with the Anton le Vei wannabees so am pondering my options spiritually-wise.