Sentence:  Religious faith can be considered a necessary condition of membership in a congregation , since the decision to join a worshiping group requires some motive force , but faith is not a sufficient condition for joining ; the presence of other <WSD>members</WSD> of similar social and economic level is the sufficient condition . 
Meaning of the word marked with <WSD> tags:  one of the persons who compose a social group (especially individuals who have joined and participate in a group organization)