There are plenty of theological issues which Christians can debate between ourselves and perhaps come up with opposing views, but there are fundamental things which must be accepted by all for the term 'Christian' to be applicable. One of these tenets is that Christ died and rose from the dead, the first fruits of all who have been and will be raised to eternal life. As Paul writes, the resurrection of Christ is the reason for our hope and if that is not believed then there is no future hope, no assurance. I heard about a Christian man recently who found it impossible to believe that there was life after death. His wife died and where then was Hope? We don't become Christians solely because we then are guaranteed life immortal, but it is a key factor!
What else does the resurrection of Jesus Christ do?
1. It proves that truth is stronger than falsehood. The resurrection proves that, although men loving lies killed Jesus, truth still prevailed.
2. It proves that good is stronger than evil. This comes out with graphic power in 'The Lion, The Witch and The Wardrobe' when Aslan defeats the malevolent power of the White Queen through his death and rebirth. If there had been no resurrection then evil would have triumphed.
3. It proves that love is stronger than hatred. Many people alive in the world today and throughout the centuries have good reason to think otherwise through the experiences they have faced in their lives from the forces of evil, but Christ on the cross and blasting out of the tomb demonstrated once and for all that love wins! The love of God conquered the hatred of mankind.
4. It proves that life is stronger than death. There were two devastating world wars in the twentieth century and many good lives were destroyed by the forces of mankind pitting themselves against each other. However, ultimately, life demonstrates its power by those who have died being restored to new eternal life in God's Kingdom where there is no pain or sadness.