Charles Ellicott Commentary 1 Corinthians 11:25

"In like manner also the cup, after supper, saying, This cup is the new covenant in my blood: this do, as often as ye drink [it], in remembrance of me." — 1 Corinthians 11:25 (ASV)

After the same manner also he took the cup, when he had supped.—We have here an intimation not found in Saint Matthew's or Saint Mark’s narrative, that the blessing of the cup took place “after supper,” which implies that the blessing of the bread took place earlier in the meal.

This cup is the new testament.—Better, This cup is the new covenant. The word “new” is peculiar to this and Saint Luke’s narrative; it does not occur in the best manuscripts of Saint Matthew and Saint Mark. The new covenant of grace between God and Humanity was ratified in the blood of Christ. The cup containing the symbol of that blood is therefore the pledge and witness of that covenant. This was a new covenant in blood (Romans 3:25) as contrasted with the old covenant in blood (Exodus 24:8).

As often as you drink.—This can scarcely be taken as a command to make all occasions of bodily refreshment virtually a eucharist, but must be regarded as referring definitely (as in the following verse) to this particular rite.