The portraits in the Book of Kells have presented art historians with a number of problems. The manuscript, as we know it, is incomplete and only three of the portrait pages have survived. Two of these are normally assumed to be representations of St Matthew and St John, largely on the strength of their position and text. The third is in a broadly similar format and may well be one of the remaining Evangelists. Mark or Luke. Unlike the Lindisfarne Gospels, none of the portraits include titles or the traditional Evangelists' symbols to assist with identification.
The Gospel of Matthew begins with a genealogy, showing Christ's descent. This portrait appears at the culmination of that list, just as Christ's name is mentioned. In addition, the peacocks in the tympanum are conventional symboys of immortality and the Resurrection, owing to the belief that their flesh was incorruptible. Beneath them, the chalices with vines represent the sacrament, as referred to at the Last Supper (Matthew 26:29). The likelihood, then is that this a portrait of Christ, although the evidence is inconclusive.