In modern scholarship, the baptism of Jesus and his crucifixion are considered to be two historically certain facts about Jesus.For example, James Dunn
states that these "two facts in the life of Jesus command almost universal assent" and "rank so high on the 'almost impossible to doubt or deny' scale of historical facts" that they are often the starting points for the study of the historical Jesus. Bart Ehrman states that the crucifixion of Jesus on the orders of Pontius Pilate is the most certain element about him.John Dominic Crossan states that the crucifixion of Jesus is as certain as any historical fact can be.Eddy and Boyd state that it is now "firmly established" that there is non-Christian confirmation of the crucifixion of Jesus.Craig Blomberg states that most scholars in the third quest for the historical Jesus consider the crucifixion indisputable.Christopher M. Tuckett states that, although the exact reasons for the death of Jesus are hard to determine, one of the indisputable facts about him is that he was crucified.
http://en.wikipedia.org/wiki/Crucifixion_of_JesusOf course the most important thing is what sinless Jesus who never lied and who lived a pure holy life said about Himself. He said many many times that He came to die on the cross to save the world. He foretold this to His desciples. Also, the Old Testament prophecied about crucifixion of Jesus hundreds of years before it happened. But beside what Jesus said and the Bible said there are historical records, witnesses which prove crucifixion as undeniable and undisputable fact. That is why when I attended a secular school and I was taught at hitory class that Jesus died on the Cross. Because cricifixion of Jesus is a historical FACT, it is historical event. So why does islam deny that? Can you tell me?