This Bible contradiction is from the Skeptic's Annotated Bible.

Verses

Satan entered Judas before the last supper.

Luke 22:3 View context

Then entered Satan into Judas surnamed Iscariot, being of the number of the twelve.

Satan entered Judas after the last supper.

John 13:27 View context

And after the sop Satan entered into him. Then said Jesus unto him, That thou doest, do quickly.