A.T. Robertson Commentary Mark 14:23

"And he took a cup, and when he had given thanks, he gave to them: and they all drank of it." — Mark 14:23 (ASV)

A cup (ποτηριον). Probably the ordinary wine of the country mixed with two-thirds water, though the word for wine (οινος) is not used here in the Gospels, but "the fruit of the vine" (εκ του γενηματος της αμπελου). See Mt 26:26-29 for discussion of important details. Mark and Matthew give substantially the same account of the institution of the Supper by Jesus, while Lu 22:17-20 agrees closely with 1 Corinthians 11:23–26 where Paul claims to have obtained his account by direct revelation from the Lord Jesus.