John Chrysostom
Catena Aurea · Markusevangelium 14
And as they did eat, Jesus took bread, and blessed, and brake it, and gave to them, and said, Take, eat: this is my body. And he took the cup, and when he had given thanks, he gave it to them: and they all drank of it. And he said unto them, This is my blood of the new testament, which is shed for many. Verily I say unto you, I will drink no more of the fruit of the vine, until that day that I drink it new in the kingdom of God.
(ubi sup.) Even now also that Christ is close to us; He who prepared that table, Himself also consecrates it. For it is not man who makes the offerings to be the Body and Blood of Christ, but Christ whowas crucified for us. The words are spoken by the mouth of the Priest, and are consecrated by the power and the grace of God. By this word which He spoke, This is my body, the offerings are consecrated; and as that word which says, Increase and multiply, and fill the earth, (Gen. 1:28) was sent forth but once, yet has its effect throughout all time, when nature does the work of generation; so also that voice was spoken once, yet gives confirmation to the sacrifice through all the tables of the Church even to this day, even to His advent.