Each Benedictine monastery handles their oblates differently. But, yes, some oblates are non-Catholic. One of the blessings of St. Benedict’s rule is that it draws Christians together.
I’m not very familiar with lay Carthusians (which technically we shouldn’t call them, since the order asked them to change their name) but their webpage indicates that they have applied to become a Private Association of the Faithful. In addition, their guidelines for participating in their Yahoo group indicates that:
Persons of all faiths are welcome on the IFSB Forum. However, the viewpoint of the Forum is that of fidelity to the living Magisterium (teaching authority) of the Roman Catholic Church. The membership is predominately Catholic. Therefore, please be respectful of this fact.
I haven’t read their messages in several months, but I believe they are still working on developing a rule for themselves. Their group is a little more free-form since the Carthusian order isn’t directly involved with them.
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