The unbelieving doctor

Holy Communion, the True Body and Blood of our Lord...

The blessed in memory Demetrios Panagopoulos (1916-1982), who was enlightened by God to preach, had even preached at the Hospital “Sotiria”, where others did not approach for the fear of tuberculosis. There he was accompanied by the priest Fr. Dimitrios Papantonis, who offered the sacrament of confession to the tuberculosis patients and celebrated the Divine Liturgy for these patients.
One day a doctor, somehow troubled, who was listening to the sermons, approached the preacher and said:
- Mr. Panagopoulos, it is impossible for the priest to consume the remaining contents of the Holy Communion from the holy chalice. So many tuberculosis patients received Holy Communion from this, and as it is well known, tuberculosis is transmitted by saliva. So what does the priest do with the Lord's Body and Blood that is left over? Does he pour it into the special drain of the church, (where holy vessels are washed so not to be desecrated)? But isn't that a great sin?
-"Such a thing never happens," the preacher countered. Christ is not infected with germs, and there is no risk of infection from the Holy Mysteries.
But the doctor could not believe it. Mr. Panagopoulos then urged him to attend the next divine service, and at the end to stand somewhere to see the priest's movements at the time of the consumption of the holy gifts. So it happened. The doctor saw with his own eyes the priest consuming the contents of the holy chalice after he had given Holy Communion to the patients. He even saw him adding wine two or three times, making sure that no trace of the Lord's Body and Blood remained in the chalice. Since then, the doctor not only believed, but also went to church and received Holy Communion with the patients.

Source: From the book "Miracles and Revelations from the Divine Liturgy" published by Holy Monastery of Parakletos. p. 153