There has been a betrayal. A brother betrayed a brother. Why did he do it?
For 30 coins? Hardly sounds worth it to guarantee the death of one of your best friends.
Pressing Jesus' hand? After three years together and Jesus not giving Judas the "strength" show he was looking for, perhaps.
Coaxed by Satan? Why not. Dude is still responsible for his actions.
I'd bet it was a lot of reasons. People rarely do things for one (and only one) reason.
Perhaps I should ask why we do it? Judas was one man but he is a bit of an example. We really don't know much about the guy. What we do know is that in some ways Jesus favored him (trusted him with the common purse - no small responsibility) and that Judas seemed to disagree with some of Jesus' methods (alabaster jar incident).
We should remember on this Friday that passing judgment on Judas also passes judgment on Peter (who rejected Jesus) and also passes judgment on ourselves.
What have you betrayed Jesus for? A girl? Money? A job? Football? Politics? Social status? Church (Pharisees did)? Family (he says something about that one too)?
There are many idols tossing bags of 30 coins our way. There are many ways Jesus' actions aren't what we want. Satan is not the only voice tempting us to stab our Lord in the back.
It is a sad day. But it is a good day too. Thankfully in the face of all those voices, Jesus is willing to face betrayal in an inexplicable way - submitting to it.