From a priest:
I need help from an ossified unreconstructed manualist!
This morning I was a concelebrant at Mass with two other priests.
After the consecration I was astounded to see a chalice with previously consecrated Precious Blood brought from the tabernacle. [?!?]
The Principal Celebrant proceded to effect the commingling with a particle in the chalice consecrated at a previous Mass, [?!?] and both he and the other priest concelebrant communicated from that chalice. I was very careful to ensure I drank from the newly consecrated chalice.
So, Father, was a valid Mass offered? Did it make any difference that one of the concelebrants drank from the newly-consecrated chalice?
It’s a practice the parish priest seems to have adopted when there is a significant over-consecration of the Precious Blood!
In my humble opinion it is a grave delict, but I think it is a matter of simple ignorance.
Ought the Ordinary be informed of this practice?
What a strange question.
Yes, I believe Mass was celebrated. The elements were consecrated, the elements were consumed. The co-mingling does not affect the validly. Consuming the Precious Blood not consecrated at that Mass sure does confuse the issue, though.
Our symbols and signs are important. They point to a greater reality. Signa point to the res. We must be careful not to confuse them.
Second, it is forbidden to reserve the Precious Blood except for an extremely narrow range of circumstances (as when a sick person cannot receive any other way).
Should the diocesan bishop be informed? I would talk first with the parish priest and show him. These references:
John Paul II’s 1980 Inestimabile donum 14:
On the other hand, the consecrated wine is to be consumed immediately after Communion and may not be kept. Care must be taken to consecrate only the amount of wine needed for Communion.
And Redemptionis Sacramentum 107:
Furthermore all will remember that once the distribution of Holy Communion during the celebration of Mass has been completed, the prescriptions of the Roman Missal are to be observed [cf GIRM 163, 249, 279, 284, 285a], and in particular, whatever may remain of the Blood of Christ must be entirely and immediately consumed by the Priest or by another minister, according to the norms, while the consecrated hosts that are left are to be consumed by the Priest at the altar or carried to the place for the reservation of the Eucharist.
Surely the reason for this strict prohibition is that a) there is far greater possibility for profanation and b) the accidents of wine can swiftly change and become corrupted, far more quickly and the accidents of bread of the Hosts that are reserved.
Furthermore, in the case of consecrating too much, the Precious Blood must never be simply poured out anywhere, not even the ground or sacrarium. That skates close to the “throwing away” of the Eucharist which incurs a latae sententiae excommunication, the lifting of which is reserved to the Holy See (not the local bishop). Priests know this or ought to know this. Since it is their duty to know this, they cannot easily plead ignorance, for their ignorance would be culpable ignorance. Lay people, once they know this, must refuse to do it if asked. Remember, excommunications can only be incurred if a person commits a mortal sin in doing the bad thing. Therefore, all the requirements for a mortal sin must apply.

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But, back to the point, if the priest insists that there must be Communion under both kinds, the solution here is NOT to consecrate too much. Better to consecrate to little and then explain the reason for the prudent caution rather than consecrate so much that it cannot be consumed even by proper ministers who are present.
If the parish priest who is reserving the Precious Blood will not stop doing so even after he has been informed, then I would inform the local bishop with a copy to the Congregation for Divine Worship in Rome.
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