This type of prepper prides himself on how prepared he is for any apocalyptic event. He finds it hard to keep his mouth shut about his food preparation, water supply, and his self-sustaining environment that he built as a whole. The problem with this is if a disaster does happen, those ill-equipped groups will surely come for these religious preppers first.
To me, the best option is to store emergency food. How much? If you have none, store enough for a few days. If you have enough for a few days, get enough for a week. How much you store depends on what time frame you think you're at risk for having to be completely independent. The early settlers of the southwest liked to store enough food for a whole year and still do to this day!