There are few things more precious to a religious person than their religion. It is such a big part of them, and something that can be represented in their photographs. A lot of the baby sessions I photograph include pictures of the little ones in their christening outfits. I often shoot these photographs against a white backdrop to keep the soft feel of the photograph. I usually also shoot a few photographs against a black backdrop, to help the detail of their outfits to stand out.
Somethings like baby baptisms, people don't think to hire a photographer for. I usually remind them when we take their newborn photos that most priests don't have a problem with a photographer being present at the baptism. It takes a lot of the stress off the parents at the baptism, they can just focus on being there with their child, instead of trying to capture the moment.
I love taking these cute Mormon (The Church of Jesus Christ of Latter Day Saints) Missionary pictures. With these pictures, you can dress up a little boy or girl in their Sunday best. Add the name tag of their mom or dad to their shirt and a Book of Mormon and you have a little missionary.
Religious props are not for every client, but it is something I bring up briefly to give them the idea if they want it. Some prop ideas include books of scripture, religious jewelry or anything else that signifies their religion to them.