Skeptical German New Testament critic Gerd Lüdemann concludes, “It may be taken as historically certain that Peter and the disciples had experiences after Jesus’ death in which Jesus appeared to them as the risen Christ.” 1
‘And if Christ has not been raised, our preaching is useless and so is your faith. More than that, we are then found to be false witnesses about God, for we have testified about God that he raised Christ from the dead. But he did not raise him if in fact the dead are not raised. For if the dead are not raised, then Christ has not been raised either. And if Christ has not been raised, your faith is futile; you are still in your sins. Then those also who have fallen asleep in Christ are lost. If only for this life we have hope in Christ, we are of all people most to be pitied.’ 1 Corinthians 15:14-19
Have you ever been asked how you came to your belief that Jesus was raised from the dead? Until a few years ago, I just took it on faith. As my circle of influence began to include younger generations and children that were growing into their teens, the patent answer was no longer acceptable. Although the inner working of the Holy Spirit is all I need; in order to discuss and evangelize, to a more ‘scientistic, verificationist, or intellectual’ audience, I again lean on the historicity of scripture to fortify my claims. We can even use the Bible, not as the inspired Word of God but as a collection of independent, ancient, historical documents.
Some arguments, as put forth by many notable Christian apologists are as follows:
1) On different occasions and under various circumstances different individuals and groups of people experienced appearances of Jesus alive from the dead. Paul listed eyewitnesses. Paul tells us that Jesus appeared to his chief disciple Peter, then to the inner circle of disciples known as the Twelve; then he appeared to a group of 500 disciples at once, then to his younger brother James, who up to that time was apparently not a believer, then to all the apostles. Finally, Paul adds, “he appeared also to me,” at the time when Paul was still a persecutor of the early Jesus movement (I Cor. 15.5-8).
Given the early date of Paul’s information as well as his personal acquaintance with the people involved, these appearances cannot be dismissed as mere legends The appearance narratives in the Gospels provide multiple, independent attestation of the appearances. For example, the appearance to Peter is attested by Luke and Paul; the appearance to the Twelve is attested by Luke, John, and Paul; and the appearance to the women is attested by Matthew and John.
The appearance narratives span such a breadth of independent sources that it cannot be reasonably denied that the earliest disciples did have such experiences.
2) According to the Criterion of Embarassment, Jesus’ appearance to women would make it highly unlikely that these appearances were contrived. Of course, the patent retort to these facts is, “The disciples accounts were hallucinations.”
Firstly, Jesus was not just seen on one occasion but on many occasions. Not just by one individual but by many persons. Not just by single persons but by actual groups of people. Not at one locale and circumstance but in many different places and under many different circumstances. This wide variety of circumstances, people, locale, and so forth, I think, simply makes the hallucination hypothesis quite improbable.
Secondly, These appearances were clearly physical and bodily appearances.
Thirdly, had the disciples seen hallucinations of Jesus, they would have seen hallucinations of Jesus glorified in Abrahams bosom or in paradise. According to Jewish teaching, this is where the souls of the righteous dead went to be with God when they died.
Finally, the hallucination hypothesis says nothing to explain the fact of the empty tomb.
So, What did the disciples see? They saw and experienced the risen King, the Lord of Lords, our Savior, and Salvation. Jesus Christ, for He has risen!
 Gerd Lüdemann, What Really Happened to Jesus?, trans. John Bowden (Louisville, Kent.: Westminster John Knox Press, 1995), p. 8.