One of the most famous hymns in Lutheran tradition is an old favorite called "A Mighty Fortress Is Our God." Written by Martin Luther in the late 1520's, it is a hymn which brings one to the very foot of the cross. It's dark lyrics supported by the tremulous and heavy melody, it sends shivers down the back as you read through the words leading us into battle against Satan and his followers. It was intended to spur to heavenly battle the defenders of the true faith against the forces of evil that were about in the world.
But those forces weren't just lurking in the 16th century, or 2000 years ago at Golgotha. We must guard our hearts and minds against those who do us harm today, just as Jesus resisted the temptations of Satan in his ministry so long ago.