“I can’t eat that,” a friend said, passing by the staple of our church’s monthly potluck: the perfectly crafted homemade macaroni and cheese from the kitchen of a church matriarch. Eating Emma’s macaroni was a ritual in our church; to not eat it might signal to the longtime churchgoer that you really weren’t one of us. But this young woman wasn’t being either ignorant or pretentious. In fact, she had a rare stomach disorder that would not allow her to eat dairy products. Had she eaten Emma’s signature dish, she would have become violently sick.

For most of us, eating is a joyful opportunity for Christian fellowship. For people like my friend, however, it can be a source of division and isolation. I (Dan) was a young pastor when this incident occurred, and it helped me realize how complicated church feasts— which serve as a visible symbol of Christian unity and identity—can be in a fallen world. Feasting together is good, but it ...