The Letter to Diognetus, written in the second century, is one of the earliest descriptions of how the early Christians lived. One very noteworthy passage says that Christians “marry like everyone else, and have children, but they do not expose their offspring. They share their meals, but not their wives. They live in the flesh, but they are not governed by the desires of the flesh. They live on earth, but their citizenship is in heaven.” Reading those lines, you might be wondering what it means for people to “expose their offspring,” since that is an expression that we do not commonly use today.