An old priest I know said he always found the idea of a private Mass to be odd. He insisted that there ought always be a congregation present because the Mass is a meal in which the Mystical Body of Christ is present and partakes of the Body and Blood of our Lord. I've put the question to several lay Catholics and they too thought the idea of a private Mass was strange. I then said, "Putting aside our Sunday obligation for a moment, would you attend a daily Mass if you, personally, were unable to receive Holy Communion for whatever reason?" Many of them said no, they wouldn't because the Mass is a meal and they wouldn't "get anything out of it" if they went but didn't receive Communion.
This notion of the Mass as a communal meal is quite common. It's not an outright error but something worse: a half truth. To be sure, there is a meal aspect to the Mass. The writings of the saints and Church Fathers are rife with metaphors of the heavenly banquet, of the food along the way (Viaticum), and the bread of angels. But we must not place the secondary aspect of the Mass into the primary place. Consider: it is permissible to receive Communion outside the context of the Mass such as administering the Last Rites to the dying or simply visiting the homebound. However, it is gravely sinful for a priest to confect one or both species of the Eucharist outside of the Mass. Why do you suppose that is?
Even the name for the Mass can change to reflect our preoccupation with the meal aspects. We speak of the Celebration of the Mass, or the Eucharistic Celebration, or the Paschal Mystery. Again, to be clear, none of these are wrong. The error is one of omission. It is first and foremost the Holy Sacrifice of the Mass. Ask yourself: why do you go to Mass at all? The formal cause, as the Scholastics would say, is because the Church says we must. But what is the final cause, or telos, or ultimate goal for going to Mass? If you think the answer is to receive Holy Communion, you've got another think coming.
The Mass is the unbloody propitiatory representation of Christ's sacrifice on Calvary to God the Father. Representing Christ's sacrifice is pleasing to God for the remission of our sins, both those Christians in the Church Militant on earth and the Church Suffering in Purgatory. All of this comes right from the Offertory prayers in the Traditional Latin Mass (the suppression of these Offertory prayers is perhaps the greatest crime of Bugnini and his committee of Protestants.) The modern Offertory speaks of bread and wine as the work of human hands. That sounds familiar...
Ruh oh Shaggy!Abel was a keeper of sheep, but Cain was a tiller of the ground.3 And in process of time it came to pass, that Cain brought of the fruit of the ground an offering unto the Lord.4 And Abel, he also brought of the firstlings of his flock and of the fat thereof. And the Lord had respect unto Abel and to his offering:5 But unto Cain and to his offering he had not respect.
The reception of Holy Communion is distinct from the sacrificial aspect of the Mass. God is pleased by the sacrifice regardless of whether anyone receives our Blessed Lord in Communion, hence private Masses being much more common before the revolution, and concelebration almost unheard of outside of priestly ordinations. Receiving Communion is for our benefit. If we focus on the benefits we get from receiving Communion and speak not at all of the unbloody Sacrifice of the Mass, then it's to be expected that the people will eventually come to regard the Mass as primarily a Communion Service, as an exercise in community building. We go to Mass to offer God the praise, love, and thanksgiving that are his due. We go to Mass to participate in the Sacrifice which is pleasing to God and is a propitiation for our sins and the sins of the Holy Souls in Purgatory. By focusing so much on the act of receiving Communion, are we not focusing on ourselves and not on God?
Again, to be clear, there are definitely aspects of a communal meal to the Mass. By losing sight of the sacrificial nature of the Mass however, we are doing a grave disservice to ourselves and more importantly to the Lord.