The bodily resurrection of Jesus of Nazareth from the dead is the crowning proof of the truth of Christianity. As the apostle Paul says in 1 Corinthians 15:17 “And if Christ has not been raised, then your faith is useless and you are still guilty of your sins.”
There are many claims in the New Testament related to this central event but not all are accepted by New Testament scholars. Dr. Gary Habermas and Dr. Mike Licona, in their book The Case for the Resurrection of Jesus, compiled a list of facts that were strongly supported (using the criteria of textual critics) and facts that were granted by virtually all scholars (from skeptics to conservative Christians.) 
One such fact was that Jesus died on the cross and was buried. Some skeptics, however, assert that Jesus’ disciples were simply mistaken. Some will argue that Jesus survived his scourging and crucifixion and only appeared to be dead.
Is This Reasonable?
Is it reasonable to believe that those who removed Jesus from the cross, transported Him to His grave, and prepared Him for burial, did not know if he were alive or dead? 
There are other problems with this theory:
- The Gospels record the fact that a guard stabbed Jesus and both blood and water poured from His body.  Pericardial effusion or pleural effusion is often caused by circulatory shock prior to death.
- The Romans were experts at crucifixion. Crucifixion was often performed to terrorize and dissuade its witnesses from perpetrating particularly heinous crimes. Victims were left on display after death as warnings to others who might attempt dissent. Crucifixion was usually intended to provide a death that was particularly slow, painful (hence the term excruciating, literally “out of crucifying”), gruesome, humiliating, and public, using whatever means were most expedient for that goal.
- Even when victims were taken down and given medical attention, they often died. Josephus recounts: “I saw many captives crucified, and remembered three of them as my former acquaintance. I was very sorry at this in my mind, and went with tears in my eyes to Titus, and told him of them; so he immediately commanded them to be taken down, and to have the greatest care taken of them, in order to their recovery; yet two of them died under the physician’s hands, while the third recovered.  Jesus, once taken down form the cross, was prepared for burial and interred. There is no record of His receiving medical attention. Even this, apparently, was no guarantee of survival.
For these and many other reasons it seems not only unreasonable but improbable that the disciples were mistaken about the death of Jesus.
 G. Habermas and M. Licona, The Case for the Resurrection of Jeus (Grand Rapids, MI: Kregel, 2004), 47.
 John 19:40-42, NIV
 John 19:34
 The Life Of Flavius Josephus, 75