According to Lutherans, under what conditions (or at what moment) do the consecrated species cease to be the blood and body of Christ?

Question

I understand that Lutherans believe in the real, physical presence of Christ in the Eucharist, but not in such a way that the species cease to be true bread and wine. So you are physically eating God, but you are also physically eating bread. (Similar to the hypostatic union of Christs two natures: Christ is fully human and fully divine. The bread is fully bread but also fully Christ).

I was wondering when the consecrated species cease to be divine and return to normal, natural, mundane matter. I heard somewhere a long time ago that Lutherans believe that the real presence only continues for duration of the liturgy and once the mass concludes the species return to being normal bread and wine; I have not been able to confirm this.

Perhaps the Lutheran view is similar to the Catholic view. That is, the sacramental union persists so long as the bread and wine are recognizable as bread and wine. Once they have gone moldy, turned to vinegar, evaporated or been digested, the body and blood are no longer present.

Answer 1

As a former Lutheran, I was taught that the belief is that the sacramental union only persists through the liturgy, although the elements are still treated with respect afterwards.

Wikipedia's description of Lutheran Eucharistic beliefs seems to confirm this:

In most Lutheran congregations, the administration of private communion of the sick and "shut-in" (those too feeble to attend services) involves a completely separate service of the Eucharist for which the sacramental elements are consecrated by the celebrant.[14]

Contrast this with Catholics, who bring the consecrated Host to the shut-ins without the need to celebrate Mass in their homes, and who have communion services when priests are unavailable and receive the consecrated Hosts which remain in the Tabernacle.

A comparison of Good Friday services also reveals important differences. Catholics do not have Mass on Good Friday, but still have communion using the Hosts in the Tabernacle. That is, Catholics do not celebrate the Eucharist, but still consume the Body and Blood of Christ. On the other hand, Lutherans have a service without communion at all. They do not celebrate the Eucharist and, thus, have no Host to consume.

Also from Wikipedia:

Lutheran Eucharistic adoration is not commonly practiced, but when it occurs it is done only from the moment of consecration to reception.

Answer 2

In Lutheran theology the sacramental union of Christ's body & blood is connected with the proper use of the sacrament. So, for example, Eucharistic elements are often taken after a church service is completed and then distributed to shut-ins (See the First Apology of Justin Martyr). The words of institution are typically repeated in homes for the sake of good communication, but the pre-consecration of the elements takes place in the worship service.

For example, the Church Order for Brandenburg published in 1540, mentions the communion of the sick in relationship to how normally, a pastor is instructed to carry the sacrament (after consecration) to the sick at the same time as the congregation communes.

The meaning of “at the same time” is to be interpreted broadly, in the sense of what Justin Martyr taught that,

…there is a distribution to each, and a participation of that over which thanks have been given, and to those who are absent a portion is sent by the deacons.

Martin Luther is quoted in a table conversation in 1540:

There are some who let the Supper be a sacrament only while it is in use. Whatever remains leftover they throw away [a reference to the practice in places like Leipzig?] ...One must not make it so precise: four or five steps or even several hours. ...Whether one or two hours has passed and a person takes it from one altar to another or carries it across the street, it nevertheless remains the body of Christ. (LW 54: 407–408)

However, with the above being said, if somebody were to come to church and pawn the Eucharistic bread/body of Christ into their pocket and then hold it hostage for some devious purpose, the proper use of the elements would not be taking place.