Is it generally accepted when a member who does not believe in a deity aims to critically question aspects of Christianity?
That could be seen as an attack against Christianity.
But it is not an attack against Christians, neither members here nor in general.
For example, somebody who wants to challenge the existence of god, could ask a question "Do angels exist?" and give an answer by himself stating that it does not and supporting it by arguments. That certainly provokes answers that disagree.
That is an open attack against the concept of Christianity, but not against the community of Christians.
It explicitly does not involve malice against a person.
I assume that individual questions challenging aspects of Christianity, are accepted. But I could understand if a member with the expressed purpose to argue against Christianity or religions in general would be not welcome.
This is not clear from the site description.
It is about cases of "understanding the Bible from the perspective of a specific viewpoint". But systematically asking such questions may be perceived by readers as an attack on the him. It is not. Could you accept that attacking the concept of religion does not imply malice? I personally state that there is no malice in it, but I can accept if it is not in the scope of this site.