Christians have long marked Jesus Christ's Last Supper on Maundy Thursday but new research by a leading academic suggests they have got the wrong date.
Professor Colin Humphreys, a scientist at the University of Cambridge, has now concluded that the final meal took place on the Wednesday before the crucifixion, a day earlier than previously accepted.
He believes his findings, which are likely to cause ripples among millions of Christians, could present a case for finally introducing a fixed date for Easter.
Not quite the Last Supper? New evidence suggests Jesus and his disciples shared the famous meal - depicted here by Leonardo Da Vinci - earlier than previously thought
They also present a solution to apparent contradictions in the Gospels and logistical issues relating to the hours before the crucifixion.
In a new book, The Mystery Of The Last Supper, Prof Humphreys uses a combination of Biblical, historical and astronomical research to address the precise nature and timing of Jesus's final meal with his disciples.
Researchers have long been puzzled by an apparently fundamental Biblical inconsistency.
While Matthew, Mark and Luke all assert that the Last Supper coincided with the start of the Jewish festival of Passover, John claims it took place before Passover.
The contradiction has presented what has been described as 'the thorniest problem in the New Testament'.
But Prof Humphreys has now concluded that Jesus - along with Matthew, Mark and Luke - may have been using a different calendar to John.
Hand of friendship: Jesus and his disciples break bread together
'Whatever you think about the Bible, the fact is that Jewish people would never mistake the Passover meal for another meal, so for the Gospels to contradict themselves in this regard is really hard to understand,' Prof Humphreys said.
'Many Biblical scholars say that, for this reason, you can't trust the Gospels at all. But if we use science and the Gospels hand in hand, we can actually prove that there was no contradiction.'
In his theory, Jesus went by an old-fashioned Jewish calendar rather than the official lunar calendar which was in widespread use at the time of his death and is still in use today.
This would put the Passover meal - and the Last Supper - on the Wednesday, explaining how a large number of events took place between the meal and the crucifixion.
It would mean Jesus' arrest, interrogation and separate trials did not all take place in the space of one night but in fact occurred over a longer time frame.
By ironing out all the perceived discrepancies in the timing of events, Prof Humphreys believes a date could be ascribed to Easter in our modern solar calendar. Working on the basis that the crucifixion took place on April 3, Easter Day would be on April 5.(dailymail.co.uk)