Photo credit: http://screenrant.com/lost-season-6-promo-image-the-last-supper-ross-40027/
Cut and pasted from Wikipedia:
The Last Supper is the final meal that, according to Christian belief, Jesus shared with his Twelve Apostles in Jerusalem before his crucifixion. The Last Supper provides the scriptural basis for the Eucharist, also known as "communion" or "the Lord's Supper".
The overall narrative of Canonical Gospels share the elements that the Last Supper took place towards the end of the week, after Jesus's triumphal entry into Jerusalem and that Jesus and his disciples shared a meal shortly before Jesus was crucified at the end of that week. During the meal Jesus predicts his betrayal by one of the disciples present, and foretells that Peter will deny knowing him later that day.
The three Synoptic Gospels and the First Epistle to the Corinthians include the account of the institution of the Eucharist (and a new covenant) in which Jesus takes bread, breaks it and gives it to the disciples, saying: "This is my body which is given for you".
The Gospel of John does not include this episode, but tells of Jesus washing the feet of the Apostles, and has a detailed Farewell discourse by Jesus, calling the Apostles who follow his teachings "friends and not servants", as he prepares them for his departure.
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