Large Catechism-pp.367-370-The Reader's Edition of the BOC
"They (Jews) acted as though the commandment were fulfilled by doing no manual work whatsoever....This commandment, therefore in its literal sense, does not apply to us Christians. It is entirely an outward matter, like other ordinances of the Old Testament." (pp.367-368, 81-82)
It is kind of shocking how Luther starts with this commandment. At first you might be thinking, "Does Luther not like the Word of God? Is he questioning God's command given on Mt. Sinai?" Well, he is first and foremonst trying to make a point. The point that if this commandment is all about what we do or not do on a specific day on our won, it is definately not Christian and not holy. I have heard these arguments concerning the Sabbath, as far as should we shop on the Sabbath, should we work, should we do this or not. And what ends up happening is a lot of doubt and concern about whether or not we are living a holy life based upon how much or little work we do.
However, Luther points us to what God was trying to emphasize from the beginning. The Sabbath is a day of rest and to make it holy it must have the Word of God (p.369, 91). "Any observance or work that is practiced without God's Word is unholy before God (p.369, 92). The Sabbath equals being in the Word, especially the day set aside for Word and Sacrament ministry in the worship service.
I would argue that the Christian church at large has a major problem with this commandment. It is no surprise to everyone that church is on Sunday each week. As far as I know, it doesn't surprise anyone to find out that church will be on Sunday. However, for some reason they have a tendency to not plan to be in God's house that day to receive the gifts. As many people tell me, "Pastor, we were just out too late on Saturday night and could not get up in time." Interesting! The question back should be, "If you had a packers game to go to on Sunday morning, would you stay out real late on Saturday night?" The answer, probably no! Why? Because it is a priority. So their faithful and honest reason for not being in worship is based upon priorities and I must admit, there was a time during college that I used the same excuses and boy were they lame!
The Third commandment is all about receiving the gifts of God in worship (Word, Sacraments, repentance, and the forgiveness of sins). God has promised to be there, and if we do not make it, it is time for us not to make excuses, but to repent and receive forgiveness.
Lord have mercy