A reading from the first apology of Justin Martyr in defense of the Christians, c. 100-165
No one may share in the Eucharist except those who believe in the truth of our teachings and have been washed in the bath which confers forgiveness of sins and rebirth, and who live according to Christ’s commands.
For we do not receive this food as ordinary bread and as ordinary drink; but just as Jesus Christ our Savior became flesh through the word of God, and assumed flesh and blood for our salvation, so too we are taught that the food over which the prayer of thanksgiving, the word received from Christ, has been said, the food which nourishes our flesh and blood by assimilation, is the flesh and blood of this Jesus who became flesh.
The apostles in their memoirs, which are called gospels, recorded that Jesus left them these instructions: he took bread, pronounced the prayer of thanksgiving, and said: “Do this in memorial of me. This is my body”.
In the same way he took the cup, pronounced the prayer of thanksgiving, and said; “This is my blood”, and shared it among them and no one else.
From that time on we have always continued to remind one another of this.
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