In chapter five of the Qur’an we find the story of the disciples’ oath in brief. That brief explanation is sufficient for those who understand. In the 112th verse, we find that the disciples asked for food from heaven but Issa (peace be upon him) initially rebuked their plea. The disciples insisted and Prophet Issa (peace be upon him) then prayed to Allah (5:114) to give them food from heaven. Allah Almighty did give them what they desired but there was a condition (5:115), which was that if any of them disbelieved after that, then he would be given a severe punishment the like of which would not be given to anyone else.
Allah said: Surely I will send it down to you, but whoever shall disbelieve afterwards from among you, surely I will chastise him with a chastisement with which I will not chastise anyone among the nations.
We do know that Issa (peace be upon him) was granted a place on a hill by Allah Almighty (23:50) and we also know that one of the disciples (Judas Iscariot) betrayed him and reported the whereabouts of Prophet Issa (peace be upon him) to the authorities. This betrayal or attempted murder of a Prophet of Allah is definitely disbelief and is liable to the punishment promised by Allah Almighty. This explains the crucifixion of Judas! However, some might argue that the punishment for Judas is in the hereafter and the one on the cross was not him. This is a reasonable argument but if we analyse it in detail, we see that it is a wrong argument. We know that the greatest punishment in hell would be given to Pharaoh and therefore, this could not be Judas. One might argue that crucifixion of Judas is not a punishment that could be labeled as ‘one like none else’. This is not a reasonable argument. The Qur’an however, does not mention about the sufferings of the man on the cross. In the Bible, he shouts, “Alah! Alah! Why have you forsaken me?” Perhaps the pain he felt was something not felt by anyone else ever. Secondly, the Gospel of Barnabas and the Apocalypse of Peter mention the punishment of Judas in some detail; he was spit at, dragged around nude in public, humiliated, degraded etc. Perhaps he was even sexually assaulted by the enemies of Prophet Issa (peace be upon him) and the dozens of soldiers.
Thirdly, his punishment is an example for the people as billions of Christians and Muslims dislike him for what he did. Lastly, if we read the words Allah Almighty has used in 5:115, we find that the one who would disbelieve would receive a punishment that no one else would receive.
Changing of the face and appearance of Judas to that of Prophet Issa (peace be upon him) definitely classifies into this category. No person has ever received such a punishment.