In First Corinthians 15, Paul strains to prove that Jesus Christ not only died, but was raised from the dead three days later. To reinforce the truth of Christ's literal death, Paul
references His entombment. To reinforce His resurrection, Paul lists eyewitnesses who saw Christ walking around post-crucifixion. Paul writes all of this in order to refute some morons among the Corinthians who didn't believe in resurrection at all.