I was a kid in the late seventies and the early eighties. At the time, Sears was a popular department store. This long-standing company sold a brand of children’s pants called “Toughskins,” named so for their sturdy fabrication, especially at the knees. Like many kids who wore Toughskins, I did my best to test their durability by falling out of trees and sliding into home base. I consistently wore the knees out. So my Mom would iron patches onto the knees to get a few more months out of them. Despite all the protection Toughskins afforded, I still came home with abrasions—red, tender, and filled with dirt. When my Mom would spray on disinfectant, there was the predictable sting, which I always figured was the chemical killing the germs. She always said it was necessary to apply disinfectant to allow the abrasion to heal properly.

The following excerpt from Luther’s 1526 Trinity Sunday sermon provides the reformer’s commentary on the new birth Christians receive through water and the Holy Spirit in the Sacrament of Holy Baptism.