The Right Religion, the Catholic Religion
The Hypothetical Doctrine of the Two Fold Promises of Christ
In Matthew 16:18, Christ promised that the gates of hell will not prevail. He did not promise we would have priests until the end of the age. Rather He promised that He would be with us.
Therefore, if we had the Eucharist, but all validly ordained priests, bishops, and the Pope dropped dead, and the valid ones who are schismatics as well died, we would still have Christ in the Eucharist. Therefore His promise would not be broken.
The same thing as if we had not bread or wine to confect the sacrament, but had priests. We would still have Christ since they are acting in his person.
Therefore, the only way the promise of Christ could fail is if we had no priests and no transubstantiated Eucharistic hosts.
Wouldn’t one have to be eternal? In this scenario, the Eucharist would succeed the priests until Christ’s coming. As long as one transubstantiated host remains the gates haven’t prevailed. The same with a priest.