Since the Lord's Table, or Eucharist, is a means of grace, and since we receive the true body and blood of Christ spiritually (see Calvin on this in his Institutes), I am surprised, even stunned, as to why most Reformed churches have the sacrament monthly.
I am not so surprised that the Zwinglians have it monthly, bi-monthly, quarterly, or yearly. (Why not once a lifetime?) But nature determines frequency. I am even more stunned at those Reformed churches who agree with Calvin's view that the Eucharist is a real means of grace and that we receive the true body and blood of Christ spiritually, but yet they have it monthly. I have even heard some try to justify this by saying "since it's such a deep means of grace we shouldn't do it often." Again, this too is stunning to me.
We cannot argue against the established fact that the early church celebrated the sacrament weekly. Acts 2:42; Acts 20:7; and 1 Corinthians 11 all indicate that the early church gathered for the purpose of enjoying the sacrament. The Reformers saw Word and Sacrament as interconnected. They saw the Sacrament as bare without the Word; and they saw the Word as bare without the sacrament. They saw the Sacrament as the visible Word of God. They saw it as the seal of the preached Word.
However, I agree that, just because the early church did something one way, it does not mean we have to do so. (We aren't necessarily supposed to greet one another with a holy kiss or have a community of goods today.)
But, having said that, since the Table is a means of grace, and since we receive the natural body and blood spiritually (as the Three Forms of Unity state), then why would someone not want the Body and Blood weekly?
The Church is the nurturing Mother of salvation. When we understand that she is the home and oasis of weak and weary pilgrims, weekly Lord's Table is a must.
It seems to me that churches that administer the sacrament less than weekly still indeed are like the nurturing mother of salvation, but is like a mother that gives her baby formula instead of breast milk. To her credit, she wants to take care of her baby, so she feeds the baby formula. But, she does not recognize the wonderful and sweet benefits of giving her baby breast milk.
It is no wonder Luther retained weekly Eucharist. I love Luther's emphasis on Law/Gospel. I love his emphasis on the theology of the cross, and that the Church is the home of weak and weary pilgrims. Is it any wonder, then, that Lutherans today have weekly Lord's Supper across the board? They correctly see the sacrament as a strengthening means of grace, as a gift from God to us. It is truly given for us.
We Reformed should learn from our Lutheran brothers.