Day 187: The Church's Sacrificial Unity

To the offering of Christ are united not only the members still here on earth, but also those already in the glory of heaven. In communion with and commemorating the Blessed Virgin Mary and all the saints, the Church offers the Eucharistic sacrifice. In the Eucharist the Church is as it were at the foot of the cross with Mary, united with the offering and intercession of Christ. CCC 1370

Today's reading from the Catechism is short, on the sacrificial unity of the Eucharist with, what has been called, the Churches Militant, Penitent, and Triumphant. The Catechism Compendium summarizes this brief reading:

In the Eucharist, the sacrifice of Christ becomes also the sacrifice of the members of his Body. The lives of the faithful, their praise, their suffering, their prayers, their work, are united to those of Christ. In as much as it is a sacrifice, the Eucharist is likewise offered for all the faithful, living and dead, in reparation for the sins of all and to obtain spiritual and temporal benefits from God. The Church in heaven is also united to the offering of Christ. (#281)

The Catechism Companion, Vol II also comments on this:

The pope and bishops are mentioned in each Mass since they represent the oneness of the Catholic Church... The Eucharistic sacrifice joins together all Catholics who are living now and also the souls in heaven... [It] serves two essential purposes: giving glory to the Father and contributing to the sanctification and salvation of the world. (p. 138)

Finally, Dr. Brant Pitre has a good video on this:

 

Angels in adoration of the Eucharist, which is presented on an altar decorated with the Last Supper. Lithograph by J. G. Schreiner after M. Seitz after H. Hess.

The [lithograph] shown here is a beautiful reminder that the Eucharistic sacrifice unites not only the members of the Church on earth but also the saints and angels. (p. 139)