John 13 is interesting to take a look at. Jesus told Peter he was clean and only needed his feet washed.
Have you ever been to a Biblical dinner? The Pastor has you sit like they would have at the last supper and through various Bible quotes and the tradition of the times he determines who sat where.
While "Da Vinci's Last Supper may be great art even after they destroyed it 'restoring it' it is technically wrong.
At the real last supper they sat at a triclinium table which is like a v and where you sit is based on who is being honored and where Peter was sitting was the place where he was the one who was supposed to wash everyone's feet. He didn't do this so Jesus did as a mild rebuke.
I highly recommend attending a Biblical Dinner if one is available in you area. Typically, they are held around Easter. The Pastor is careful to note the tradition of the time as well as Scripture to support his conjecture on table settings. It's really cool and the food is awesome.
On another note, someone questioned whether Judas was judged for what he did when he actually facilitated what had to happen. I've asked more than one Pastor this question and the best answer is I don't know.