Tomorrow is Maundy Thursday – the name coming either from the Latin for the 'new commandment' or 'mandatum novum' Jesus gave his disciples at the Last Supper, or the old English 'maunds' traditionally given to beggars.
That makes today, Wednesday, a likely candidate for the day Judas decided to betray Jesus. For this reason, today's known as Spy Wednesday in some Christian traditions.
But why did he do it? We don't know how long he had been with Jesus, but the core group of disciples seems to have been long-established. Something caused him to turn on Jesus right at the end.
Matthew (26: 14-16) seems to link his betrayal to the story of the woman who anointed Jesus with perfume. The disciples complained of the waste, and Judas offers to sell Jesus for 30 pieces of silver. Mark is the same (14: 10-11). Luke says that 'Satan entered Judas'; he too mentions money (22: 1-6).
In John, the link with money is clear: he says it was Judas who objected to the anointing by Mary, 'not because he cared about the poor but because he was a thief; as keeper of the money bag, he used to help himself to what was in it' (John 12:6). And in John's telling, 'Satan entered into him' at the Last Supper and Jesus told him, 'What you are about to do, do quickly' (13:27).
There has been plenty of speculation about Judas. Some have thought that perhaps he was disappointed by Jesus – he joined up expecting him to be a war leader who would drive out the Romans, and found a very different kind of Messiah.
Others have suggested he might have been trying to provoke Jesus into declaring himself – surely he would not submit tamely to being arrested by the Romans.
But perhaps the truth is simpler and sadder: just as the Gospels seem to hint, it was money that was his downfall. We don't need to look for complicated spiritual reasons. He put material security and physical comforts before the greatest opportunity anyone could ever be given: to love and serve the King of Kings, God come in the flesh.
The consequence was that Judas is remembered forever for the worst thing he did in his life.
But we should not be too quick to judge him. If we look for unique reasons for his betrayal of Jesus, it's perhaps so that we don't have to consider how very ordinary they were – and that we don't have to look too hard at ourselves.
We don't like to put ourselves on a level with Judas, but we too betray Christ for very ordinary reasons – lust, laziness and greed among them. The history of the church, in the past and the present, is littered with people who put their own desires for money, sex and power before their love for him.
Yes, Judas betrayed Jesus – but perhaps we should be more compassionate towards him than we usually are. The shocking truth is that none of us can know we wouldn't have done the same.
Follow Mark Woods on Twitter: @RevMarkWoods