Mediator Dei presents more teaching on lay participation in the Mass. First a preamble:
79. The august sacrifice of the altar is, as it were, the supreme instrument whereby the merits won by the divine Redeemer upon the cross are distributed to the faithful: “as often as this commemorative sacrifice is offered, there is wrought the work of our Redemption.”[Roman Missal, Secret of the Ninth Sunday after Pentecost] This, however, so far from lessening the dignity of the actual sacrifice on Calvary, rather proclaims and renders more manifest its greatness and its necessity, as the Council of Trent declares.[Cf. Sess. 22, c. 2. and can. 4] Its daily immolation reminds us that there is no salvation except in the cross of our Lord Jesus Christ[Cf. Gal. 6:14] and that God Himself wishes that there should be a continuation of this sacrifice “from the rising of the sun till the going down thereof,”[Mal. 1:11] so that there may be no cessation of the hymn of praise and thanksgiving which (people owe) to God, seeing that (people) required His help continually and has need of the blood of the Redeemer to remit sin which challenges God’s justice.
Bishops are responsible for faith formation with regard to the importance of being engaged in the liturgy:
80. It is, therefore, desirable, Venerable Brethren, that all the faithful should be aware that to participate in the eucharistic sacrifice is their chief duty and supreme dignity, and that not in an inert and negligent fashion, giving way to distractions and day-dreaming, but with such earnestness and concentration that they may be united as closely as possible with the High Priest, according to the Apostle, “Let this mind be in you which was also in Christ Jesus.”[Phil. 2:5] And together with Him and through Him let them make their oblation, and in union with Him let them offer up themselves.
This gives some important insight as to the later development of Sacrosanctum Concilium and the importance of participation.
Passivity is criticized for leading to distraction.
- The two qualities sought for are “earnestness” and “concentration,” which make for a good start.
- Why is participation important? Unity with Christ.
My sense is that the addition of the assembly to the rubrics for Mass serves to focus this earnestness a bit, and to ritualize the importance of union with the Lord. Rubrics are not a cure-all. And a pope’s passing responsibility to bishops is not sure-fire. But this is a root of later reform, no doubt.