What is a resurrection?
This is when a dead person returns to life again.
So the resurrection of Jesus is when Jesus died and then returned to life again.
Why should we believe that such a miracle happened when we have never seen such a miracle actually take place?
We may have never seen a miracle take place, but many people have seen miracles. We need to test these claims just as we would any claim.
Why do some people refuse to believe any miracle claim?
Because miracles are impossible in their worldview. If someone does not believe in a deity, then no miracle is possible. They will deny any miracle claim before they even hear it since miracles are impossible in their worldview. See here for more on this.
What claim did the disciples make after Jesus had died on the cross?
The disciples claimed to have been witnesses of Jesus’ resurrection. After Jesus had ascended to heaven, they came together to find a replacement for Judas. The reason for this action was to find someone who would serve with them as a witness to Jesus’ resurrection.
Therefore, it is necessary that of the men who have accompanied us all the time that the Lord Jesus went in and out among us–beginning with the baptism of John until the day that He was taken up from us–one of these must become a witness with us of His resurrection. So they put forward two men… (Acts 1:21-23)
Did the disciples actually witness Jesus’ resurrection?
They did not. By the words, “a witness with us of His resurrection,” they mean someone who saw Jesus alive after His crucifixion and burial, not someone who actually saw Jesus come out of the sepulcher.
Why was the resurrection important to the disciples?
The resurrection was at the center of the apostles’ preaching. The reason for this was that the resurrection was God’s way of identifying Jesus as the Messiah-king for whom the Jews were waiting and expecting. Peter argues on the day of Pentecost that Jesus was the Messiah. He bases this claim on the fact that God raised Jesus from the dead, a fact to which they were eyewitnesses. (Acts 2:24, 32) He does the same thing after the healing of the lame man. (Acts 3:15) When Peter defends the apostles before the Sanhedrin, he claims that “there is salvation in no one else; for there is no other name under heaven that has been given among men by which we must be saved.” (Acts 4:12) This claim, he again bases on the fact that God raised Jesus from the dead. (Acts 4:10)