Ambrose of Milan — as excerpted in the Catena Aurea on Luke 4:22-27

“Now in a mystery the people pollute the Church, that another people might succeed, gathered together from foreigners, leprous indeed at first before it is baptized in the mystical stream, but which after the sacrament of baptism, washed from the stains of body and soul, begins to be a virgin without spot or wrinkle.”