The sainted Dr. C.F.W. Walther, the first president of the LCMS, offered these thoughts about worship in a sermon...
To (a Christian, Sunday) is the most precious day of the entire week, when he can step back from the daily grind and rejoice. He would not give up his dear Sunday, when he is permitted rest, for all of the world's goods and money.
On the Sabbath, the true Christian studies God's Word. He reads it, hears it, considers it, and speaks with others about it. The true Christian not only hears God's Word with his ears, but he is also sanctified by it, increasing in knowledge, in faith, in love, in hope, in humility, in patience and in all other Christian virtues. For this reason, he prays to God, going to and leaving from church that he might continue to grow in His Word.
Oh, when the observance of the Sabbath happens in a Christian manner, then each Sunday illumines all other days with its heavenly shine, the pearl and crown of all days, the right Sabbath eve on earth, after which will come the eternal Sabbath in heaven.