How about what the disbelieving Jews have done to Christ (PBUH), by helping the Roman soldiers, as claimed, to crucify him (according to the Christian belief)? (See Matthew 26: 47-75) Were they obeying or disobeying God by doing so? If they were obeying God, then the Jews who crucified Christ (PBUH) deserve a reward from God for their obedience, just like any other obeying believers. In fact, nearly all Christians agree that the Jews were the greatest sinners among men and the worst creatures of God. Not only that, but they also curse them and would go on to the extent of permitting the shedding of their blood.
They have designated a time to persecute the Jews at the last days of their fasting to commemorate the days of crucifixion. Moreover, if those Jews were disobedient, could not God prevent them from crucifying Christ? If God could not, then He would not be able to prevent Satan from oppressing the coming generations. If God could prevent people from committing sins and He did not, then He was able to stop Satan with no need for such a scheme to deceive him.
On the other hand, if the act of crucifixion were approved by God, then it would be alright to give Satan the ability to oppress the children of Adam (PBUH) in the past and in the future.
Therefore, there would have been no need for God to deceive Satan.
By now, we have come to realize that there is no doubt that any mature person will recognize the corruption that has come to Christianity. The purpose here is to explain some of the discrepancies that they have as excuses for themselves in order not to accept believing in Allah, in His book (The Qur'an), in His Prophet (Mohammed (PBUH)) and in His religion (Al-Islam). Allah is just and does not order people to believe in or do what they can not. God, praise be to Him, has never asked people for anything that is beyond their ability. It is unfortunate that Christians continue to attribute unspeakable injustice to God. No believer has ever done so before.
 Let us look at what Maryam Jameelah (a former Jewish woman) has written about the enmity Christians have against Jews. Maryam Jameelah, Islam in Theory and Practice. (H. Farooq Associates LTD., Lahore, 1983) p.1.
"From a very early age, I wondered what I being Jewish really meant. I suppose I first began to wonder when at Easter-time Christian classmates at school called me "Christ Killer". As soon as the Easter season had passed, they were miraculously transformed into friendly play mates for the remainder of the year. When I once asked a little Roman Catholic boy in my class why he did this, he said that the priest had told him to".
 Fasting was prescribed to the Christians in the Bible as in: "When you fast do not look somber as hypocrites do" (Matthew 6:16) Who observes fasting nowadays?
 Ibn Taymiyah, p.218.