Apparently, some Europeans tried to demonstrate superior faith by rejecting medicines and making no effort to avoid places and persons infected with plague. This is not trusting God but tempting him. God has created medicines and provided us with intelligence to guard and take good care of the body so that we can live in good health. In the same way, anyone who carelessly acquired the plague and infected others was considered a murderer, as was the person who, having apparently recovered from plague, passed the disease to others before he was completely free of the germs. Luther suggested that communities seek ways to isolate victims of plague, just as God in the Old Testament ordered lepers to be banished from the city.
Isolation is better for everyone.
The ill may still be cared for, and the infection will not spread. Our plague here in Wittenberg has been caused by nothing but filth. The air, thank God, is still clean and pure, but some few have been contaminated because of the laziness or recklessness of some. Many popular beliefs about the dead held that poison vapors and mists rise out of graves. Luther suggested graveyards be moved for the common health of cities and because burial grounds should be sacred, hallowed places, not small plots in alleys or outside marketplaces.