The last meal, which Christ took with the disciples in Jerusalem before his arrest, and at which he announced to the Twelve that one of them would betray him, has been widely represented in Christian art from early times. The meal was a celebration of the Jewish feast of the Passover - the 'festival of freedom' commemorating the exodus of the Israelites from Egypt. To Christians the words of Christ as he consecrated the bread and wine mark the inauguration of the central rite of the Church. The two aspects of the theme—the announcement of the betrayal, and the first Communion of the apostles—in turn predominate at different periods of art. The early Church depicted the sacrament, first seen in a fully developed form in Byzantine mosaics of the 6th cent. The disciples are arranged round the curved side of a D-shaped table, Christ at one end. They neither sit nor stand but recline, propped on the left elbow, leaving the right arm free, as was the later Jewish custom in observing the Passover ritual. (Originally the Passover meal was taken standing, just as the Israelites stood to eat in haste on the eve of the exodus. In Roman times a recumbent posture at meals was the mark of the free man and was therefore regarded as more appropriate to the Jewish festival of freedom.) This feature recurs in the 17th cent. in the work of Poussin. In Renaissance painting the disciples are seated, usually at a rectangular table, and Christ, in their midst, is performing the actions of the priest. A chalice, the Eucharistic vessel, stands on the table before him. He is in the act of consecrating a loaf or handing a communion wafer to one of the Twelve. It is not necessarily represented as unleavened bread, as is required in the Jewish rite. Certain Old Testament themes that were traditionally regarded as prefiguring the Last Supper may be found in association with it, namely The meeting of Abraham and Melchizedek, The Passover, The gathering of manna, Elijah visited by an angel. This sacramental interpretation of the Last Supper was eclipsed at the end of the 15th cent. by Leonardo who turned away from doctrine to depict the human drama that sprang from Christ's announcement that he would be betrayed by one of those present. Leonardo's work, though the most famous, was not the first to adopt the alternative treatment of the theme. It was already to be seen in the decoration of 14th and 15th cent. refectories and churches. It prevailed until the Counter-Reformation when the Church's emphasis on the Seven Sacraments, the Eucharist in particular, restored the former version to favor. There was now greater freedom of treatment with additional figures - servants going to and fro bearing dishes and angels hovering overhead. The disciples, especially among northern painters, are characterizations of the humble folk of the time. A basin and towel discarded on the floor are a reminder of the earlier episode of Washing the disciples' feet. A dog may sit at the feet of Judas; a convention difficult to account for since the animal normally symbolizes fidelity. In representations of the announcement of the betrayal, or the 'historical' Last Supper, the main elements are the reaction of the disciples to Christ's words, and the part played by Judas. "In truth, in very truth I tell you, one of you is going to betray me". The disciples looked at one another in bewilderment: whom could he be speaking of?' There is no chalice. Christ sits at the center of a long table, his hands outspread in a way that seems to imply resignation. The disciples on either side of him turn to one another with mystification, amazement or denial on their faces and in their gestures. Judas is distinguished in several ways. In early Renaissance examples he sits on the opposite side of the table from the rest and may be in the act of taking the sop of bread from Christ. ("'Lord who is it?" Jesus replied, "It is the man to whom I give this piece of bread when I have dipped it in the dish."' (John 13:26.)) Or Judas dips his own hand. ('It is one of the Twelve who is dipping into the same bowl with me'. (Mark 14:20.) Judas is generally dark-haired and bearded, his expression sly. When the disciples are depicted with haloes that of Judas may be black, or he may be without one. He often holds a purse, perhaps in allusion to the thirty pieces of silver, the price of the betrayal, or more simply because according to John 'Judas was in charge of the common purse'.

In the 12th and 13th centuries artists made little attempt to differentiate between the disciples, with the exception of Judas. In works of later periods it is possible to identify at least the chief disciples, occasionally all, with a fair degree of certainty. Though the Twelve are shown without their personal attributes artists have tended to adhere to certain conventions as to their physical appearance and grouping. John, 'the disciple whom Jesus loved', is usually next to Christ and may sit with his head resting on the Savior's breast. ('He reclined, leaned back close to Jesus and asked, "Lord, who is it?"' (John 13:25.) He is depicted as young, clean-shaven, with long hair and sometimes rather effeminate features. Peter's characteristics are well-known: hair gray, generally short and curly and a short usually curly beard; his complexion is rubicund as befits a fisherman. He generally wears a blue cloak over a gold robe. He may hold a knife, perhaps in anticipation of the incident of the cutting off of the servant's ear in the scene of the betrayal. He sits near or next to Christ, a sign of his seniority among the disciples. Andrew is an aged man with flowing gray hair and a long gray, sometimes forked, beard. James the Less resembles Christ as to his features and the style of his hair and beard since he was traditionally identified with the apostle whom St Paul called 'James the Lord's brother' (Gal. 1: 19). For the remainder identification is less straightforward. James the Greater, somewhat older than his namesake, was, like him, related to Christ and is therefore sometimes also made to resemble him physically. As one of the three closest to the Savior during his lifetime he generally sits near him at table. Philip and Thomas are, like John, among the youngest and are usually clean-shaven. They are sometimes placed on opposite sides of the picture at either end of the table. Simon and Jude according to the more popular tradition were brothers and were among the shepherds to whom the angel announced the Nativity. They are therefore customarily depicted as old men, and sit side by side. Bartholomew has very dark, perhaps black hair and usually a beard, in which respect he may resemble Matthew. The accepted identity of the Twelve in the Last Supper of Leonardo is as follows, reading from left to right: Bartholomew, James the Less, Andrew, Judas, Peter (behind), John, (Christ), Thomas (behind), James the Greater, Philip, Matthew, Jude, Simon.