The conflict perspective would argue that the person within the religious institution is either fighting against the status quo in the society or trying to keep it in place. A member of a mainstream religion would be working to ensure that people have values and beliefs that would tend to support the status quo. A member of an "outsider" religious group (say, for example, a member of the black church) would be trying to use religious rhetoric to change society.
The symbolic interactionist perspective would be much different. It would not have any set view of a person in a religious institution. Instead, it would look at how that person (and their religious sect) sees the world. It would say that this person could be in the institution for any number of reasons. The person could be using religion as self-help. The person could be using religion as a way to find an identity. There could be any number of ways to see the person since symbolic interactionism is more concerned with how individuals perceive the world and how this affects their behavior.